Merge pull request #2686 from NoelDeMartin/MOBILE-3320

Mobile 3320

src/addons/badges/badges-lazy.module.ts

@@ -48,8 +48,8 @@ const tabletRoutes: Routes = [
 ];
 
 const routes: Routes = [
-    ...conditionalRoutes(mobileRoutes, () => CoreScreen.instance.isMobile),
-    ...conditionalRoutes(tabletRoutes, () => CoreScreen.instance.isTablet),
+    ...conditionalRoutes(mobileRoutes, () => CoreScreen.isMobile),
+    ...conditionalRoutes(tabletRoutes, () => CoreScreen.isTablet),
 ];
 
 @NgModule({

src/addons/badges/badges.module.ts

@@ -41,10 +41,10 @@ const mainMenuRoutes: Routes = [
             multi: true,
             deps: [],
             useFactory: () => () => {
-                CoreContentLinksDelegate.instance.registerHandler(AddonBadgesMyBadgesLinkHandler.instance);
-                CoreContentLinksDelegate.instance.registerHandler(AddonBadgesBadgeLinkHandler.instance);
-                CoreUserDelegate.instance.registerHandler(AddonBadgesUserHandler.instance);
-                CorePushNotificationsDelegate.instance.registerClickHandler(AddonBadgesPushClickHandler.instance);
+                CoreContentLinksDelegate.registerHandler(AddonBadgesMyBadgesLinkHandler.instance);
+                CoreContentLinksDelegate.registerHandler(AddonBadgesBadgeLinkHandler.instance);
+                CoreUserDelegate.registerHandler(AddonBadgesUserHandler.instance);
+                CorePushNotificationsDelegate.registerClickHandler(AddonBadgesPushClickHandler.instance);
             },
         },
     ],

src/addons/badges/pages/issued-badge/issued-badge.ts

@@ -54,9 +54,9 @@ export class AddonBadgesIssuedBadgePage implements OnInit {
         this.route.queryParams.subscribe(() => {
             this.badgeLoaded = false;
 
-            this.courseId = CoreNavigator.instance.getRouteNumberParam('courseId') || this.courseId; // Use 0 for site badges.
-            this.userId = CoreNavigator.instance.getRouteNumberParam('userId') || CoreSites.instance.getCurrentSite()!.getUserId();
-            this.badgeHash = CoreNavigator.instance.getRouteParam('badgeHash') || '';
+            this.courseId = CoreNavigator.getRouteNumberParam('courseId') || this.courseId; // Use 0 for site badges.
+            this.userId = CoreNavigator.getRouteNumberParam('userId') || CoreSites.getCurrentSite()!.getUserId();
+            this.badgeHash = CoreNavigator.getRouteParam('badgeHash') || '';
 
             this.fetchIssuedBadge().finally(() => {
                 this.badgeLoaded = true;
@@ -70,12 +70,12 @@ export class AddonBadgesIssuedBadgePage implements OnInit {
      * @return Promise resolved when done.
      */
     async fetchIssuedBadge(): Promise<void> {
-        this.currentTime = CoreTimeUtils.instance.timestamp();
+        this.currentTime = CoreTimeUtils.timestamp();
 
-        this.user = await CoreUser.instance.getProfile(this.userId, this.courseId, true);
+        this.user = await CoreUser.getProfile(this.userId, this.courseId, true);
 
         try {
-            const badges = await AddonBadges.instance.getUserBadges(this.courseId, this.userId);
+            const badges = await AddonBadges.getUserBadges(this.courseId, this.userId);
             const badge = badges.find((badge) => this.badgeHash == badge.uniquehash);
 
             if (!badge) {
@@ -85,14 +85,14 @@ export class AddonBadgesIssuedBadgePage implements OnInit {
             this.badge = badge;
             if (badge.courseid) {
                 try {
-                    this.course = await CoreCourses.instance.getUserCourse(badge.courseid, true);
+                    this.course = await CoreCourses.getUserCourse(badge.courseid, true);
                 } catch {
                     // Maybe an old deleted course.
                     this.course = undefined;
                 }
             }
         } catch (message) {
-            CoreDomUtils.instance.showErrorModalDefault(message, 'Error getting badge data.');
+            CoreDomUtils.showErrorModalDefault(message, 'Error getting badge data.');
         }
     }
 
@@ -102,11 +102,11 @@ export class AddonBadgesIssuedBadgePage implements OnInit {
      * @param refresher Refresher.
      */
     async refreshBadges(refresher?: CustomEvent<IonRefresher>): Promise<void> {
-        await CoreUtils.instance.ignoreErrors(Promise.all([
-            AddonBadges.instance.invalidateUserBadges(this.courseId, this.userId),
+        await CoreUtils.ignoreErrors(Promise.all([
+            AddonBadges.invalidateUserBadges(this.courseId, this.userId),
         ]));
 
-        await CoreUtils.instance.ignoreErrors(Promise.all([
+        await CoreUtils.ignoreErrors(Promise.all([
             this.fetchIssuedBadge(),
         ]));
 

src/addons/badges/pages/user-badges/user-badges.ts

@@ -40,7 +40,7 @@ export class AddonBadgesUserBadgesPage implements AfterViewInit, OnDestroy {
 
     constructor(route: ActivatedRoute) {
         const courseId = parseInt(route.snapshot.queryParams.courseId ?? 0); // Use 0 for site badges.
-        const userId = parseInt(route.snapshot.queryParams.userId ?? CoreSites.instance.getCurrentSiteUserId());
+        const userId = parseInt(route.snapshot.queryParams.userId ?? CoreSites.getCurrentSiteUserId());
 
         this.badges = new AddonBadgesUserBadgesManager(AddonBadgesUserBadgesPage, courseId, userId);
     }
@@ -67,8 +67,8 @@ export class AddonBadgesUserBadgesPage implements AfterViewInit, OnDestroy {
      * @param refresher Refresher.
      */
     async refreshBadges(refresher?: IonRefresher): Promise<void> {
-        await CoreUtils.instance.ignoreErrors(AddonBadges.instance.invalidateUserBadges(this.badges.courseId, this.badges.userId));
-        await CoreUtils.instance.ignoreErrors(this.fetchBadges());
+        await CoreUtils.ignoreErrors(AddonBadges.invalidateUserBadges(this.badges.courseId, this.badges.userId));
+        await CoreUtils.ignoreErrors(this.fetchBadges());
 
         refresher?.complete();
     }
@@ -77,12 +77,12 @@ export class AddonBadgesUserBadgesPage implements AfterViewInit, OnDestroy {
      * Obtain the initial list of badges.
      */
     private async fetchInitialBadges(): Promise<void> {
-        this.currentTime = CoreTimeUtils.instance.timestamp();
+        this.currentTime = CoreTimeUtils.timestamp();
 
         try {
             await this.fetchBadges();
         } catch (message) {
-            CoreDomUtils.instance.showErrorModalDefault(message, 'Error loading badges');
+            CoreDomUtils.showErrorModalDefault(message, 'Error loading badges');
 
             this.badges.setItems([]);
         }
@@ -92,7 +92,7 @@ export class AddonBadgesUserBadgesPage implements AfterViewInit, OnDestroy {
      * Update the list of badges.
      */
     private async fetchBadges(): Promise<void> {
-        const badges = await AddonBadges.instance.getUserBadges(this.badges.courseId, this.badges.userId);
+        const badges = await AddonBadges.getUserBadges(this.badges.courseId, this.badges.userId);
 
         this.badges.setItems(badges);
     }

src/addons/badges/services/badges.ts

@@ -37,7 +37,7 @@ export class AddonBadgesProvider {
      * @return Promise resolved with true if enabled, false otherwise.
      */
     async isPluginEnabled(siteId?: string): Promise<boolean> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return site.canUseAdvancedFeature('enablebadges') && site.wsAvailable('core_course_get_user_navigation_options');
     }
@@ -63,7 +63,7 @@ export class AddonBadgesProvider {
      */
     async getUserBadges(courseId: number, userId: number, siteId?: string): Promise<AddonBadgesUserBadge[]> {
 
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const data: AddonBadgesGetUserBadgesWSParams = {
             courseid: courseId,
             userid: userId,
@@ -101,14 +101,14 @@ export class AddonBadgesProvider {
      * @return Promise resolved when data is invalidated.
      */
     async invalidateUserBadges(courseId: number, userId: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKey(this.getBadgesCacheKey(courseId, userId));
     }
 
 }
 
-export class AddonBadges extends makeSingleton(AddonBadgesProvider) {}
+export const AddonBadges = makeSingleton(AddonBadgesProvider);
 
 /**
  * Params of core_badges_get_user_badges WS.

src/addons/badges/services/handlers/badge-link.ts

@@ -43,7 +43,7 @@ export class AddonBadgesBadgeLinkHandlerService extends CoreContentLinksHandlerB
 
         return [{
             action: (siteId: string): void => {
-                CoreNavigator.instance.navigateToSitePath(`/badges/${params.hash}`, { siteId });
+                CoreNavigator.navigateToSitePath(`/badges/${params.hash}`, { siteId });
             },
         }];
     }
@@ -59,9 +59,9 @@ export class AddonBadgesBadgeLinkHandlerService extends CoreContentLinksHandlerB
      * @return Whether the handler is enabled for the URL and site.
      */
     isEnabled(siteId: string): Promise<boolean> {
-        return AddonBadges.instance.isPluginEnabled(siteId);
+        return AddonBadges.isPluginEnabled(siteId);
     }
 
 }
 
-export class AddonBadgesBadgeLinkHandler extends makeSingleton(AddonBadgesBadgeLinkHandlerService) {}
+export const AddonBadgesBadgeLinkHandler = makeSingleton(AddonBadgesBadgeLinkHandlerService);

src/addons/badges/services/handlers/mybadges-link.ts

@@ -37,7 +37,7 @@ export class AddonBadgesMyBadgesLinkHandlerService extends CoreContentLinksHandl
     getActions(): CoreContentLinksAction[] {
         return [{
             action: (siteId: string): void => {
-                CoreNavigator.instance.navigateToSitePath('/badges', { siteId });
+                CoreNavigator.navigateToSitePath('/badges', { siteId });
             },
         }];
     }
@@ -50,9 +50,9 @@ export class AddonBadgesMyBadgesLinkHandlerService extends CoreContentLinksHandl
      * @return Whether the handler is enabled for the URL and site.
      */
     async isEnabled(siteId: string): Promise<boolean> {
-        return AddonBadges.instance.isPluginEnabled(siteId);
+        return AddonBadges.isPluginEnabled(siteId);
     }
 
 }
 
-export class AddonBadgesMyBadgesLinkHandler extends makeSingleton(AddonBadgesMyBadgesLinkHandlerService) {}
+export const AddonBadgesMyBadgesLinkHandler = makeSingleton(AddonBadgesMyBadgesLinkHandlerService);

src/addons/badges/services/handlers/push-click.ts

@@ -40,9 +40,9 @@ export class AddonBadgesPushClickHandlerService implements CorePushNotifications
     async handles(notification: CorePushNotificationsNotificationBasicData): Promise<boolean> {
         const data = notification.customdata || {};
 
-        if (CoreUtils.instance.isTrueOrOne(notification.notif) && notification.moodlecomponent == 'moodle' &&
+        if (CoreUtils.isTrueOrOne(notification.notif) && notification.moodlecomponent == 'moodle' &&
                 (notification.name == 'badgerecipientnotice' || (notification.name == 'badgecreatornotice' && data.hash))) {
-            return AddonBadges.instance.isPluginEnabled(notification.site);
+            return AddonBadges.isPluginEnabled(notification.site);
         }
 
         return false;
@@ -59,7 +59,7 @@ export class AddonBadgesPushClickHandlerService implements CorePushNotifications
 
         if (data.hash) {
             // We have the hash, open the badge directly.
-            await CoreNavigator.instance.navigateToSitePath(`/badges/${data.hash}`, {
+            await CoreNavigator.navigateToSitePath(`/badges/${data.hash}`, {
                 siteId: notification.site,
             });
 
@@ -67,17 +67,17 @@ export class AddonBadgesPushClickHandlerService implements CorePushNotifications
         }
 
         // No hash, open the list of user badges.
-        await CoreUtils.instance.ignoreErrors(
-            AddonBadges.instance.invalidateUserBadges(
+        await CoreUtils.ignoreErrors(
+            AddonBadges.invalidateUserBadges(
                 0,
                 Number(notification.usertoid),
                 notification.site,
             ),
         );
 
-        await CoreNavigator.instance.navigateToSitePath('/badges', { siteId: notification.site });
+        await CoreNavigator.navigateToSitePath('/badges', { siteId: notification.site });
     }
 
 }
 
-export class AddonBadgesPushClickHandler extends makeSingleton(AddonBadgesPushClickHandlerService) {}
+export const AddonBadgesPushClickHandler = makeSingleton(AddonBadgesPushClickHandlerService);

src/addons/badges/services/handlers/user.ts

@@ -37,7 +37,7 @@ export class AddonBadgesUserHandlerService implements CoreUserProfileHandler {
      * @return Always enabled.
      */
     isEnabled(): Promise<boolean> {
-        return AddonBadges.instance.isPluginEnabled();
+        return AddonBadges.isPluginEnabled();
     }
 
     /**
@@ -73,7 +73,7 @@ export class AddonBadgesUserHandlerService implements CoreUserProfileHandler {
             action: (event, user, courseId): void => {
                 event.preventDefault();
                 event.stopPropagation();
-                CoreNavigator.instance.navigateToSitePath('/badges', {
+                CoreNavigator.navigateToSitePath('/badges', {
                     params: CoreObject.withoutEmpty({ courseId, userId: user.id }),
                 });
             },
@@ -82,4 +82,4 @@ export class AddonBadgesUserHandlerService implements CoreUserProfileHandler {
 
 }
 
-export class AddonBadgesUserHandler extends makeSingleton(AddonBadgesUserHandlerService) {}
+export const AddonBadgesUserHandler = makeSingleton(AddonBadgesUserHandlerService);

src/addons/block/activitymodules/activitymodules.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockActivityModulesComponentsModule } from './components/componen
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockActivityModulesHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockActivityModulesHandler.instance);
             },
         },
     ],

src/addons/block/activitymodules/components/activitymodules/activitymodules.ts

@@ -45,7 +45,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
      * @return Resolved when done.
      */
     protected async invalidateContent(): Promise<void> {
-        await CoreCourse.instance.invalidateSections(this.instanceId);
+        await CoreCourse.invalidateSections(this.instanceId);
     }
 
     /**
@@ -54,7 +54,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
      * @return Promise resolved when done.
      */
     protected async fetchContent(): Promise<void> {
-        const sections = await CoreCourse.instance.getSections(this.getCourseId(), false, true);
+        const sections = await CoreCourse.getSections(this.getCourseId(), false, true);
 
         this.entries = [];
         const archetypes: Record<string, number> = {};
@@ -66,7 +66,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
             }
 
             section.modules.forEach((mod) => {
-                if (mod.uservisible === false || !CoreCourse.instance.moduleHasView(mod) ||
+                if (mod.uservisible === false || !CoreCourse.moduleHasView(mod) ||
                     typeof modFullNames[mod.modname] != 'undefined') {
                     // Ignore this module.
                     return;
@@ -74,7 +74,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
 
                 // Get the archetype of the module type.
                 if (typeof archetypes[mod.modname] == 'undefined') {
-                    archetypes[mod.modname] = CoreCourseModuleDelegate.instance.supportsFeature<number>(
+                    archetypes[mod.modname] = CoreCourseModuleDelegate.supportsFeature<number>(
                         mod.modname,
                         CoreConstants.FEATURE_MOD_ARCHETYPE,
                         CoreConstants.MOD_ARCHETYPE_OTHER,
@@ -85,7 +85,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
                 if (archetypes[mod.modname] == CoreConstants.MOD_ARCHETYPE_RESOURCE) {
                     // All resources are gathered in a single "Resources" option.
                     if (!modFullNames['resources']) {
-                        modFullNames['resources'] = Translate.instance.instant('core.resources');
+                        modFullNames['resources'] = Translate.instant('core.resources');
                     }
                 } else {
                     modFullNames[mod.modname] = mod.modplural;
@@ -94,14 +94,14 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
             });
         });
         // Sort the modnames alphabetically.
-        modFullNames = CoreUtils.instance.sortValues(modFullNames);
+        modFullNames = CoreUtils.sortValues(modFullNames);
         for (const modName in modFullNames) {
             let icon: string;
 
             if (modName === 'resources') {
-                icon = CoreCourse.instance.getModuleIconSrc('page', modIcons['page']);
+                icon = CoreCourse.getModuleIconSrc('page', modIcons['page']);
             } else {
-                icon = CoreCourseModuleDelegate.instance.getModuleIconSrc(modName, modIcons[modName]);
+                icon = CoreCourseModuleDelegate.getModuleIconSrc(modName, modIcons[modName]);
             }
 
             this.entries.push({
@@ -122,7 +122,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
             return this.instanceId;
         }
 
-        return CoreSites.instance.getCurrentSiteHomeId();
+        return CoreSites.getCurrentSiteHomeId();
     }
 
     /**
@@ -131,7 +131,7 @@ export class AddonBlockActivityModulesComponent extends CoreBlockBaseComponent i
      * @param entry Selected entry.
      */
     gotoCoureListModType(entry: AddonBlockActivityModuleEntry): void {
-        CoreNavigator.instance.navigateToSitePath('course/list-mod-type', {
+        CoreNavigator.navigateToSitePath('course/list-mod-type', {
             params: {
                 courseId: this.getCourseId(),
                 modName: entry.modName,

src/addons/block/activitymodules/services/block-handler.ts

@@ -43,4 +43,4 @@ export class AddonBlockActivityModulesHandlerService extends CoreBlockBaseHandle
 
 }
 
-export class AddonBlockActivityModulesHandler extends makeSingleton(AddonBlockActivityModulesHandlerService) {}
+export const AddonBlockActivityModulesHandler = makeSingleton(AddonBlockActivityModulesHandlerService);

src/addons/block/activityresults/activityresults.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockActivityResultsComponentsModule } from './components/componen
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockActivityResultsHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockActivityResultsHandler.instance);
             },
         },
     ],

src/addons/block/activityresults/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockActivityResultsHandlerService extends CoreBlockBaseHandle
 
 }
 
-export class AddonBlockActivityResultsHandler extends makeSingleton(AddonBlockActivityResultsHandlerService) {}
+export const AddonBlockActivityResultsHandler = makeSingleton(AddonBlockActivityResultsHandlerService);

src/addons/block/badges/badges.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockBadgesComponentsModule } from './components/components.module
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockBadgesHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockBadgesHandler.instance);
             },
         },
     ],

src/addons/block/badges/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockBadgesHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockBadgesHandler extends makeSingleton(AddonBlockBadgesHandlerService) {}
+export const AddonBlockBadgesHandler = makeSingleton(AddonBlockBadgesHandlerService);

src/addons/block/blogmenu/blogmenu.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockBlogMenuComponentsModule } from './components/components.modu
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockBlogMenuHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockBlogMenuHandler.instance);
             },
         },
     ],

src/addons/block/blogmenu/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockBlogMenuHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockBlogMenuHandler extends makeSingleton(AddonBlockBlogMenuHandlerService) {}
+export const AddonBlockBlogMenuHandler = makeSingleton(AddonBlockBlogMenuHandlerService);

src/addons/block/blogrecent/blogrecent.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockBlogRecentComponentsModule } from './components/components.mo
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockBlogRecentHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockBlogRecentHandler.instance);
             },
         },
     ],

src/addons/block/blogrecent/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockBlogRecentHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockBlogRecentHandler extends makeSingleton(AddonBlockBlogRecentHandlerService) {}
+export const AddonBlockBlogRecentHandler = makeSingleton(AddonBlockBlogRecentHandlerService);

src/addons/block/blogtags/blogtags.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockBlogTagsComponentsModule } from './components/components.modu
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockBlogTagsHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockBlogTagsHandler.instance);
             },
         },
     ],

src/addons/block/blogtags/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockBlogTagsHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockBlogTagsHandler extends makeSingleton(AddonBlockBlogTagsHandlerService) {}
+export const AddonBlockBlogTagsHandler = makeSingleton(AddonBlockBlogTagsHandlerService);

src/addons/block/calendarmonth/calendarmonth.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockCalendarMonthHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockCalendarMonthHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockCalendarMonthHandler.instance);
             },
         },
     ],

src/addons/block/calendarmonth/services/block-handler.ts

@@ -45,11 +45,11 @@ export class AddonBlockCalendarMonthHandlerService extends CoreBlockBaseHandler
             title: 'addon.block_calendarmonth.pluginname',
             class: 'addon-block-calendar-month',
             component: CoreBlockOnlyTitleComponent,
-            link: AddonCalendar.instance.getMainCalendarPagePath(),
+            link: AddonCalendar.getMainCalendarPagePath(),
             linkParams: linkParams,
         };
     }
 
 }
 
-export class AddonBlockCalendarMonthHandler extends makeSingleton(AddonBlockCalendarMonthHandlerService) {}
+export const AddonBlockCalendarMonthHandler = makeSingleton(AddonBlockCalendarMonthHandlerService);

src/addons/block/calendarupcoming/calendarupcoming.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockCalendarUpcomingHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockCalendarUpcomingHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockCalendarUpcomingHandler.instance);
             },
         },
     ],

src/addons/block/calendarupcoming/services/block-handler.ts

@@ -45,11 +45,11 @@ export class AddonBlockCalendarUpcomingHandlerService extends CoreBlockBaseHandl
             title: 'addon.block_calendarupcoming.pluginname',
             class: 'addon-block-calendar-upcoming',
             component: CoreBlockOnlyTitleComponent,
-            link: AddonCalendar.instance.getMainCalendarPagePath(),
+            link: AddonCalendar.getMainCalendarPagePath(),
             linkParams: linkParams,
         };
     }
 
 }
 
-export class AddonBlockCalendarUpcomingHandler extends makeSingleton(AddonBlockCalendarUpcomingHandlerService) {}
+export const AddonBlockCalendarUpcomingHandler = makeSingleton(AddonBlockCalendarUpcomingHandlerService);

src/addons/block/comments/comments.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockCommentsHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockCommentsHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockCommentsHandler.instance);
             },
         },
     ],

src/addons/block/comments/services/block-handler.ts

@@ -50,4 +50,4 @@ export class AddonBlockCommentsHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockCommentsHandler extends makeSingleton(AddonBlockCommentsHandlerService) {}
+export const AddonBlockCommentsHandler = makeSingleton(AddonBlockCommentsHandlerService);

src/addons/block/completionstatus/completionstatus.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockCompletionStatusHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockCompletionStatusHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockCompletionStatusHandler.instance);
             },
         },
     ],

src/addons/block/completionstatus/services/block-handler.ts

@@ -52,4 +52,4 @@ export class AddonBlockCompletionStatusHandlerService extends CoreBlockBaseHandl
 
 }
 
-export class AddonBlockCompletionStatusHandler extends makeSingleton(AddonBlockCompletionStatusHandlerService) {}
+export const AddonBlockCompletionStatusHandler = makeSingleton(AddonBlockCompletionStatusHandlerService);

src/addons/block/glossaryrandom/glossaryrandom.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockGlossaryRandomHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockGlossaryRandomHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockGlossaryRandomHandler.instance);
             },
         },
     ],

src/addons/block/glossaryrandom/services/block-handler.ts

@@ -45,4 +45,4 @@ export class AddonBlockGlossaryRandomHandlerService extends CoreBlockBaseHandler
 
 }
 
-export class AddonBlockGlossaryRandomHandler extends makeSingleton(AddonBlockGlossaryRandomHandlerService) {}
+export const AddonBlockGlossaryRandomHandler = makeSingleton(AddonBlockGlossaryRandomHandlerService);

src/addons/block/html/html.module.ts

@@ -22,7 +22,7 @@ import { AddonBlockHtmlHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockHtmlHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockHtmlHandler.instance);
             },
         },
     ],

src/addons/block/html/services/block-handler.ts

@@ -46,4 +46,4 @@ export class AddonBlockHtmlHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockHtmlHandler extends makeSingleton(AddonBlockHtmlHandlerService) {}
+export const AddonBlockHtmlHandler = makeSingleton(AddonBlockHtmlHandlerService);

src/addons/block/learningplans/learningplans.module.ts

@@ -30,7 +30,7 @@ import { CoreBlockComponentsModule } from '@features/block/components/components
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockLearningPlansHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockLearningPlansHandler.instance);
             },
         },
     ],

src/addons/block/learningplans/services/block-handler.ts

@@ -45,4 +45,4 @@ export class AddonBlockLearningPlansHandlerService extends CoreBlockBaseHandler
 
 }
 
-export class AddonBlockLearningPlansHandler extends makeSingleton(AddonBlockLearningPlansHandlerService) {}
+export const AddonBlockLearningPlansHandler = makeSingleton(AddonBlockLearningPlansHandlerService);

src/addons/block/myoverview/components/myoverview/myoverview.ts

@@ -148,15 +148,15 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
      */
     async ngOnInit(): Promise<void> {
         // Refresh the enabled flags if enabled.
-        this.downloadCourseEnabled = !CoreCourses.instance.isDownloadCourseDisabledInSite();
-        this.downloadCoursesEnabled = !CoreCourses.instance.isDownloadCoursesDisabledInSite();
+        this.downloadCourseEnabled = !CoreCourses.isDownloadCourseDisabledInSite();
+        this.downloadCoursesEnabled = !CoreCourses.isDownloadCoursesDisabledInSite();
 
         // Refresh the enabled flags if site is updated.
         this.updateSiteObserver = CoreEvents.on(CoreEvents.SITE_UPDATED, () => {
-            this.downloadCourseEnabled = !CoreCourses.instance.isDownloadCourseDisabledInSite();
-            this.downloadCoursesEnabled = !CoreCourses.instance.isDownloadCoursesDisabledInSite();
+            this.downloadCourseEnabled = !CoreCourses.isDownloadCourseDisabledInSite();
+            this.downloadCoursesEnabled = !CoreCourses.isDownloadCoursesDisabledInSite();
 
-        }, CoreSites.instance.getCurrentSiteId());
+        }, CoreSites.getCurrentSiteId());
 
         this.coursesObserver = CoreEvents.on(
             CoreCoursesProvider.EVENT_MY_COURSES_UPDATED,
@@ -166,10 +166,10 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
                     this.refreshCourseList();
                 }
             },
-            CoreSites.instance.getCurrentSiteId(),
+            CoreSites.getCurrentSiteId(),
         );
 
-        this.currentSite = CoreSites.instance.getCurrentSite();
+        this.currentSite = CoreSites.getCurrentSite();
 
         const promises: Promise<void>[] = [];
         if (this.currentSite) {
@@ -209,16 +209,16 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
         const promises: Promise<void>[] = [];
 
         // Invalidate course completion data.
-        promises.push(CoreCourses.instance.invalidateUserCourses().finally(() =>
-            CoreUtils.instance.allPromises(this.courseIds.map((courseId) =>
-                AddonCourseCompletion.instance.invalidateCourseCompletion(courseId)))));
+        promises.push(CoreCourses.invalidateUserCourses().finally(() =>
+            CoreUtils.allPromises(this.courseIds.map((courseId) =>
+                AddonCourseCompletion.invalidateCourseCompletion(courseId)))));
 
-        promises.push(CoreCourseOptionsDelegate.instance.clearAndInvalidateCoursesOptions());
+        promises.push(CoreCourseOptionsDelegate.clearAndInvalidateCoursesOptions());
         if (this.courseIds.length > 0) {
-            promises.push(CoreCourses.instance.invalidateCoursesByField('ids', this.courseIds.join(',')));
+            promises.push(CoreCourses.invalidateCoursesByField('ids', this.courseIds.join(',')));
         }
 
-        await CoreUtils.instance.allPromises(promises).finally(() => {
+        await CoreUtils.allPromises(promises).finally(() => {
             this.prefetchIconsInitialized = false;
         });
     }
@@ -233,7 +233,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
 
         const showCategories = config?.displaycategories?.value == '1';
 
-        const courses = await CoreCoursesHelper.instance.getUserCoursesWithOptions(this.sort, undefined, undefined, showCategories);
+        const courses = await CoreCoursesHelper.getUserCoursesWithOptions(this.sort, undefined, undefined, showCategories);
 
         // Check to show sort by short name only if the text is visible.
         if (courses.length > 0) {
@@ -300,7 +300,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
             false,
         );
         if (this.showFilters.custom == 'show') {
-            this.customFilter = CoreTextUtils.instance.parseJSON(config?.customfieldsexport?.value, []);
+            this.customFilter = CoreTextUtils.parseJSON(config?.customfieldsexport?.value, []);
         } else {
             this.customFilter = [];
         }
@@ -372,7 +372,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
 
         Object.keys(this.prefetchCoursesData).forEach(async (filter) => {
             this.prefetchCoursesData[filter] =
-                await CoreCourseHelper.instance.initPrefetchCoursesIcons(this.courses[filter], this.prefetchCoursesData[filter]);
+                await CoreCourseHelper.initPrefetchCoursesIcons(this.courses[filter], this.prefetchCoursesData[filter]);
         });
     }
 
@@ -386,10 +386,10 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
         const initialIcon = this.prefetchCoursesData[selected].icon;
 
         try {
-            await CoreCourseHelper.instance.prefetchCourses(this.courses[selected], this.prefetchCoursesData[selected]);
+            await CoreCourseHelper.prefetchCourses(this.courses[selected], this.prefetchCoursesData[selected]);
         } catch (error) {
             if (!this.isDestroyed) {
-                CoreDomUtils.instance.showErrorModalDefault(error, 'core.course.errordownloadingcourse', true);
+                CoreDomUtils.showErrorModalDefault(error, 'core.course.errordownloadingcourse', true);
                 this.prefetchCoursesData[selected].icon = initialIcon;
             }
         }
@@ -404,7 +404,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
         CoreEvents.trigger(CoreCoursesProvider.EVENT_MY_COURSES_REFRESHED);
 
         try {
-            await CoreCourses.instance.invalidateUserCourses();
+            await CoreCourses.invalidateUserCourses();
         } catch (error) {
             // Ignore errors.
         }
@@ -435,7 +435,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
 
             this.loaded = false;
             try {
-                const courses = await CoreCourses.instance.getEnrolledCoursesByCustomField(filterName, filterValue);
+                const courses = await CoreCourses.getEnrolledCoursesByCustomField(filterName, filterValue);
 
                 // Get the courses information from allincludinghidden to get the max info about the course.
                 const courseIds = courses.map((course) => course.id);
@@ -443,7 +443,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
                 this.filteredCourses = this.courses.allincludinghidden.filter((allCourse) =>
                     courseIds.indexOf(allCourse.id) !== -1);
             } catch (error) {
-                CoreDomUtils.instance.showErrorModalDefault(error, this.fetchContentDefaultError);
+                CoreDomUtils.showErrorModalDefault(error, this.fetchContentDefaultError);
             } finally {
                 this.loaded = true;
             }
@@ -500,7 +500,7 @@ export class AddonBlockMyOverviewComponent extends CoreBlockBaseComponent implem
         this.courses.favourite = [];
         this.courses.hidden = [];
 
-        const today = CoreTimeUtils.instance.timestamp();
+        const today = CoreTimeUtils.timestamp();
         courses.forEach((course) => {
             if (course.hidden) {
                 this.courses.hidden.push(course);

src/addons/block/myoverview/myoverview.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockMyOverviewHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockMyOverviewHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockMyOverviewHandler.instance);
             },
         },
     ],

src/addons/block/myoverview/services/block-handler.ts

@@ -35,8 +35,8 @@ export class AddonBlockMyOverviewHandlerService extends CoreBlockBaseHandler {
      * @return Whether or not the handler is enabled on a site level.
      */
     async isEnabled(): Promise<boolean> {
-        return (CoreSites.instance.getCurrentSite()?.isVersionGreaterEqualThan('3.6')) ||
-            !CoreCourses.instance.isMyCoursesDisabledInSite();
+        return (CoreSites.getCurrentSite()?.isVersionGreaterEqualThan('3.6')) ||
+            !CoreCourses.isMyCoursesDisabledInSite();
     }
 
     /**
@@ -55,4 +55,4 @@ export class AddonBlockMyOverviewHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockMyOverviewHandler extends makeSingleton(AddonBlockMyOverviewHandlerService) {}
+export const AddonBlockMyOverviewHandler = makeSingleton(AddonBlockMyOverviewHandlerService);

src/addons/block/newsitems/newsitems.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockNewsItemsComponentsModule } from './components/components.mod
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockNewsItemsHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockNewsItemsHandler.instance);
             },
         },
     ],

src/addons/block/newsitems/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockNewsItemsHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockNewsItemsHandler extends makeSingleton(AddonBlockNewsItemsHandlerService) {}
+export const AddonBlockNewsItemsHandler = makeSingleton(AddonBlockNewsItemsHandlerService);

src/addons/block/onlineusers/onlineusers.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockOnlineUsersComponentsModule } from './components/components.m
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockOnlineUsersHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockOnlineUsersHandler.instance);
             },
         },
     ],

src/addons/block/onlineusers/services/block-handler.ts

@@ -43,4 +43,4 @@ export class AddonBlockOnlineUsersHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockOnlineUsersHandler extends makeSingleton(AddonBlockOnlineUsersHandlerService) {}
+export const AddonBlockOnlineUsersHandler = makeSingleton(AddonBlockOnlineUsersHandlerService);

src/addons/block/privatefiles/privatefiles.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockPrivateFilesHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockPrivateFilesHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockPrivateFilesHandler.instance);
             },
         },
     ],

src/addons/block/privatefiles/services/block-handler.ts

@@ -46,4 +46,4 @@ export class AddonBlockPrivateFilesHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockPrivateFilesHandler extends makeSingleton(AddonBlockPrivateFilesHandlerService) {}
+export const AddonBlockPrivateFilesHandler = makeSingleton(AddonBlockPrivateFilesHandlerService);

src/addons/block/recentactivity/recentactivity.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockRecentActivityComponentsModule } from './components/component
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockRecentActivityHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockRecentActivityHandler.instance);
             },
         },
     ],

src/addons/block/recentactivity/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockRecentActivityHandlerService extends CoreBlockBaseHandler
 
 }
 
-export class AddonBlockRecentActivityHandler extends makeSingleton(AddonBlockRecentActivityHandlerService) {}
+export const AddonBlockRecentActivityHandler = makeSingleton(AddonBlockRecentActivityHandlerService);

src/addons/block/recentlyaccessedcourses/components/recentlyaccessedcourses/recentlyaccessedcourses.ts

@@ -64,15 +64,15 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
     async ngOnInit(): Promise<void> {
 
         // Refresh the enabled flags if enabled.
-        this.downloadCourseEnabled = !CoreCourses.instance.isDownloadCourseDisabledInSite();
-        this.downloadCoursesEnabled = !CoreCourses.instance.isDownloadCoursesDisabledInSite();
+        this.downloadCourseEnabled = !CoreCourses.isDownloadCourseDisabledInSite();
+        this.downloadCoursesEnabled = !CoreCourses.isDownloadCoursesDisabledInSite();
 
         // Refresh the enabled flags if site is updated.
         this.updateSiteObserver = CoreEvents.on(CoreEvents.SITE_UPDATED, () => {
-            this.downloadCourseEnabled = !CoreCourses.instance.isDownloadCourseDisabledInSite();
-            this.downloadCoursesEnabled = !CoreCourses.instance.isDownloadCoursesDisabledInSite();
+            this.downloadCourseEnabled = !CoreCourses.isDownloadCourseDisabledInSite();
+            this.downloadCoursesEnabled = !CoreCourses.isDownloadCoursesDisabledInSite();
 
-        }, CoreSites.instance.getCurrentSiteId());
+        }, CoreSites.getCurrentSiteId());
 
         this.coursesObserver = CoreEvents.on(
             CoreCoursesProvider.EVENT_MY_COURSES_UPDATED,
@@ -83,7 +83,7 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
                 }
             },
 
-            CoreSites.instance.getCurrentSiteId(),
+            CoreSites.getCurrentSiteId(),
         );
 
         super.ngOnInit();
@@ -107,17 +107,17 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
     protected async invalidateContent(): Promise<void> {
         const promises: Promise<void>[] = [];
 
-        promises.push(CoreCourses.instance.invalidateUserCourses().finally(() =>
+        promises.push(CoreCourses.invalidateUserCourses().finally(() =>
             // Invalidate course completion data.
-            CoreUtils.instance.allPromises(this.courseIds.map((courseId) =>
-                AddonCourseCompletion.instance.invalidateCourseCompletion(courseId)))));
+            CoreUtils.allPromises(this.courseIds.map((courseId) =>
+                AddonCourseCompletion.invalidateCourseCompletion(courseId)))));
 
-        promises.push(CoreCourseOptionsDelegate.instance.clearAndInvalidateCoursesOptions());
+        promises.push(CoreCourseOptionsDelegate.clearAndInvalidateCoursesOptions());
         if (this.courseIds.length > 0) {
-            promises.push(CoreCourses.instance.invalidateCoursesByField('ids', this.courseIds.join(',')));
+            promises.push(CoreCourses.invalidateCoursesByField('ids', this.courseIds.join(',')));
         }
 
-        await CoreUtils.instance.allPromises(promises).finally(() => {
+        await CoreUtils.allPromises(promises).finally(() => {
             this.prefetchIconsInitialized = false;
         });
     }
@@ -131,7 +131,7 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
         const showCategories = this.block.configsRecord && this.block.configsRecord.displaycategories &&
             this.block.configsRecord.displaycategories.value == '1';
 
-        this.courses = await CoreCoursesHelper.instance.getUserCoursesWithOptions('lastaccess', 10, undefined, showCategories);
+        this.courses = await CoreCoursesHelper.getUserCoursesWithOptions('lastaccess', 10, undefined, showCategories);
         this.initPrefetchCoursesIcons();
     }
 
@@ -144,7 +144,7 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
         CoreEvents.trigger(CoreCoursesProvider.EVENT_MY_COURSES_REFRESHED);
 
         try {
-            await CoreCourses.instance.invalidateUserCourses();
+            await CoreCourses.invalidateUserCourses();
         } catch (error) {
             // Ignore errors.
         }
@@ -163,7 +163,7 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
 
         this.prefetchIconsInitialized = true;
 
-        this.prefetchCoursesData = await CoreCourseHelper.instance.initPrefetchCoursesIcons(this.courses, this.prefetchCoursesData);
+        this.prefetchCoursesData = await CoreCourseHelper.initPrefetchCoursesIcons(this.courses, this.prefetchCoursesData);
     }
 
     /**
@@ -178,7 +178,7 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
             return true;
         }
 
-        if (data.action == CoreCoursesProvider.ACTION_VIEW && data.courseId != CoreSites.instance.getCurrentSiteHomeId() &&
+        if (data.action == CoreCoursesProvider.ACTION_VIEW && data.courseId != CoreSites.getCurrentSiteHomeId() &&
                 this.courses[0] && data.courseId != this.courses[0].id) {
             // Update list if user viewed a course that isn't the most recent one and isn't site home.
             return true;
@@ -216,10 +216,10 @@ export class AddonBlockRecentlyAccessedCoursesComponent extends CoreBlockBaseCom
         const initialIcon = this.prefetchCoursesData.icon;
 
         try {
-            return CoreCourseHelper.instance.prefetchCourses(this.courses, this.prefetchCoursesData);
+            return CoreCourseHelper.prefetchCourses(this.courses, this.prefetchCoursesData);
         } catch (error) {
             if (!this.isDestroyed) {
-                CoreDomUtils.instance.showErrorModalDefault(error, 'core.course.errordownloadingcourse', true);
+                CoreDomUtils.showErrorModalDefault(error, 'core.course.errordownloadingcourse', true);
                 this.prefetchCoursesData.icon = initialIcon;
             }
         }

src/addons/block/recentlyaccessedcourses/recentlyaccessedcourses.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockRecentlyAccessedCoursesHandler } from './services/block-handl
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockRecentlyAccessedCoursesHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockRecentlyAccessedCoursesHandler.instance);
             },
         },
     ],

src/addons/block/recentlyaccessedcourses/services/block-handler.ts

@@ -43,4 +43,4 @@ export class AddonBlockRecentlyAccessedCoursesHandlerService extends CoreBlockBa
 
 }
 
-export class AddonBlockRecentlyAccessedCoursesHandler extends makeSingleton(AddonBlockRecentlyAccessedCoursesHandlerService) {}
+export const AddonBlockRecentlyAccessedCoursesHandler = makeSingleton(AddonBlockRecentlyAccessedCoursesHandlerService);

src/addons/block/recentlyaccesseditems/components/recentlyaccesseditems/recentlyaccesseditems.ts

@@ -48,7 +48,7 @@ export class AddonBlockRecentlyAccessedItemsComponent extends CoreBlockBaseCompo
      * @return Resolved when done.
      */
     protected async invalidateContent(): Promise<void> {
-        await AddonBlockRecentlyAccessedItems.instance.invalidateRecentItems();
+        await AddonBlockRecentlyAccessedItems.invalidateRecentItems();
     }
 
     /**
@@ -57,7 +57,7 @@ export class AddonBlockRecentlyAccessedItemsComponent extends CoreBlockBaseCompo
      * @return Promise resolved when done.
      */
     protected async fetchContent(): Promise<void> {
-        this.items = await AddonBlockRecentlyAccessedItems.instance.getRecentItems();
+        this.items = await AddonBlockRecentlyAccessedItems.getRecentItems();
     }
 
     /**
@@ -70,13 +70,13 @@ export class AddonBlockRecentlyAccessedItemsComponent extends CoreBlockBaseCompo
         e.preventDefault();
         e.stopPropagation();
 
-        const url = CoreTextUtils.instance.decodeHTMLEntities(item.viewurl);
-        const modal = await CoreDomUtils.instance.showModalLoading();
+        const url = CoreTextUtils.decodeHTMLEntities(item.viewurl);
+        const modal = await CoreDomUtils.showModalLoading();
 
         try {
-            const treated = await CoreContentLinksHelper.instance.handleLink(url);
+            const treated = await CoreContentLinksHelper.handleLink(url);
             if (!treated) {
-                return CoreSites.instance.getCurrentSite()?.openInBrowserWithAutoLoginIfSameSite(url);
+                return CoreSites.getCurrentSite()?.openInBrowserWithAutoLoginIfSameSite(url);
             }
         } finally {
             modal.dismiss();

src/addons/block/recentlyaccesseditems/recentlyaccesseditems.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockRecentlyAccessedItemsHandler } from './services/block-handler
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockRecentlyAccessedItemsHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockRecentlyAccessedItemsHandler.instance);
             },
         },
     ],

src/addons/block/recentlyaccesseditems/services/block-handler.ts

@@ -46,4 +46,4 @@ export class AddonBlockRecentlyAccessedItemsHandlerService extends CoreBlockBase
 
 }
 
-export class AddonBlockRecentlyAccessedItemsHandler extends makeSingleton(AddonBlockRecentlyAccessedItemsHandlerService) {}
+export const AddonBlockRecentlyAccessedItemsHandler = makeSingleton(AddonBlockRecentlyAccessedItemsHandlerService);

src/addons/block/recentlyaccesseditems/services/recentlyaccesseditems.ts

@@ -43,7 +43,7 @@ export class AddonBlockRecentlyAccessedItemsProvider {
      * @return Promise resolved when the info is retrieved.
      */
     async getRecentItems(siteId?: string): Promise<AddonBlockRecentlyAccessedItemsItem[]> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const preSets: CoreSiteWSPreSets = {
             cacheKey: this.getRecentItemsCacheKey(),
@@ -53,9 +53,9 @@ export class AddonBlockRecentlyAccessedItemsProvider {
             await site.read('block_recentlyaccesseditems_get_recent_items', undefined, preSets);
 
         return items.map((item) => {
-            const modicon = item.icon && CoreDomUtils.instance.getHTMLElementAttribute(item.icon, 'src');
+            const modicon = item.icon && CoreDomUtils.getHTMLElementAttribute(item.icon, 'src');
 
-            item.iconUrl = CoreCourse.instance.getModuleIconSrc(item.modname, modicon || undefined);
+            item.iconUrl = CoreCourse.getModuleIconSrc(item.modname, modicon || undefined);
 
             return item;
         });
@@ -68,13 +68,13 @@ export class AddonBlockRecentlyAccessedItemsProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateRecentItems(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKey(this.getRecentItemsCacheKey());
     }
 
 }
-export class AddonBlockRecentlyAccessedItems extends makeSingleton(AddonBlockRecentlyAccessedItemsProvider) {}
+export const AddonBlockRecentlyAccessedItems = makeSingleton(AddonBlockRecentlyAccessedItemsProvider);
 
 
 /**

src/addons/block/rssclient/rssclient.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockRssClientComponentsModule } from './components/components.mod
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockRssClientHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockRssClientHandler.instance);
             },
         },
     ],

src/addons/block/rssclient/services/block-handler.ts

@@ -46,4 +46,4 @@ export class AddonBlockRssClientHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockRssClientHandler extends makeSingleton(AddonBlockRssClientHandlerService) {}
+export const AddonBlockRssClientHandler = makeSingleton(AddonBlockRssClientHandlerService);

src/addons/block/selfcompletion/selfcompletion.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockSelfCompletionHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockSelfCompletionHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockSelfCompletionHandler.instance);
             },
         },
     ],

src/addons/block/selfcompletion/services/block-handler.ts

@@ -50,4 +50,4 @@ export class AddonBlockSelfCompletionHandlerService extends CoreBlockBaseHandler
 
 }
 
-export class AddonBlockSelfCompletionHandler extends makeSingleton(AddonBlockSelfCompletionHandlerService) {}
+export const AddonBlockSelfCompletionHandler = makeSingleton(AddonBlockSelfCompletionHandlerService);

src/addons/block/sitemainmenu/components/sitemainmenu/sitemainmenu.ts

@@ -45,7 +45,7 @@ export class AddonBlockSiteMainMenuComponent extends CoreBlockBaseComponent impl
      * Component being initialized.
      */
     async ngOnInit(): Promise<void> {
-        this.siteHomeId = CoreSites.instance.getCurrentSiteHomeId();
+        this.siteHomeId = CoreSites.getCurrentSiteHomeId();
 
         super.ngOnInit();
     }
@@ -58,12 +58,12 @@ export class AddonBlockSiteMainMenuComponent extends CoreBlockBaseComponent impl
     protected async invalidateContent(): Promise<void> {
         const promises: Promise<void>[] = [];
 
-        promises.push(CoreCourse.instance.invalidateSections(this.siteHomeId));
-        promises.push(CoreSiteHome.instance.invalidateNewsForum(this.siteHomeId));
+        promises.push(CoreCourse.invalidateSections(this.siteHomeId));
+        promises.push(CoreSiteHome.invalidateNewsForum(this.siteHomeId));
 
         if (this.mainMenuBlock && this.mainMenuBlock.modules) {
             // Invalidate modules prefetch data.
-            promises.push(CoreCourseModulePrefetchDelegate.instance.invalidateModules(this.mainMenuBlock.modules, this.siteHomeId));
+            promises.push(CoreCourseModulePrefetchDelegate.invalidateModules(this.mainMenuBlock.modules, this.siteHomeId));
         }
 
         await Promise.all(promises);
@@ -75,14 +75,14 @@ export class AddonBlockSiteMainMenuComponent extends CoreBlockBaseComponent impl
      * @return Promise resolved when done.
      */
     protected async fetchContent(): Promise<void> {
-        const sections = await CoreCourse.instance.getSections(this.siteHomeId, false, true);
+        const sections = await CoreCourse.getSections(this.siteHomeId, false, true);
 
         const mainMenuBlock = sections.find((section) => section.section == 0);
         if (!mainMenuBlock) {
             return;
         }
 
-        const currentSite = CoreSites.instance.getCurrentSite();
+        const currentSite = CoreSites.getCurrentSite();
         const config = currentSite ? currentSite.getStoredConfig() || {} : {};
         if (!config.frontpageloggedin) {
             return;
@@ -91,7 +91,7 @@ export class AddonBlockSiteMainMenuComponent extends CoreBlockBaseComponent impl
         const items = config.frontpageloggedin.split(',');
         const hasNewsItem = items.find((item) => parseInt(item, 10) == FrontPageItemNames['NEWS_ITEMS']);
 
-        const result = CoreCourseHelper.instance.addHandlerDataForModules(
+        const result = CoreCourseHelper.addHandlerDataForModules(
             [mainMenuBlock],
             this.siteHomeId,
             undefined,
@@ -107,7 +107,7 @@ export class AddonBlockSiteMainMenuComponent extends CoreBlockBaseComponent impl
 
         // Remove forum activity (news one only) from the main menu block to prevent duplicates.
         try {
-            const forum = await CoreSiteHome.instance.getNewsForum(this.siteHomeId);
+            const forum = await CoreSiteHome.getNewsForum(this.siteHomeId);
             // Search the module that belongs to site news.
             const forumIndex =
                 this.mainMenuBlock.modules.findIndex((mod) => mod.modname == 'forum' && mod.instance == forum.id);

src/addons/block/sitemainmenu/services/block-handler.ts

@@ -43,4 +43,4 @@ export class AddonBlockSiteMainMenuHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockSiteMainMenuHandler extends makeSingleton(AddonBlockSiteMainMenuHandlerService) {}
+export const AddonBlockSiteMainMenuHandler = makeSingleton(AddonBlockSiteMainMenuHandlerService);

src/addons/block/sitemainmenu/sitemainmenu.module.ts

@@ -28,7 +28,7 @@ import { AddonBlockSiteMainMenuHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockSiteMainMenuHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockSiteMainMenuHandler.instance);
             },
         },
     ],

src/addons/block/starredcourses/components/starredcourses/starredcourses.ts

@@ -63,15 +63,15 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
      */
     async ngOnInit(): Promise<void> {
         // Refresh the enabled flags if enabled.
-        this.downloadCourseEnabled = !CoreCourses.instance.isDownloadCourseDisabledInSite();
-        this.downloadCoursesEnabled = !CoreCourses.instance.isDownloadCoursesDisabledInSite();
+        this.downloadCourseEnabled = !CoreCourses.isDownloadCourseDisabledInSite();
+        this.downloadCoursesEnabled = !CoreCourses.isDownloadCoursesDisabledInSite();
 
         // Refresh the enabled flags if site is updated.
         this.updateSiteObserver = CoreEvents.on(CoreEvents.SITE_UPDATED, () => {
-            this.downloadCourseEnabled = !CoreCourses.instance.isDownloadCourseDisabledInSite();
-            this.downloadCoursesEnabled = !CoreCourses.instance.isDownloadCoursesDisabledInSite();
+            this.downloadCourseEnabled = !CoreCourses.isDownloadCourseDisabledInSite();
+            this.downloadCoursesEnabled = !CoreCourses.isDownloadCoursesDisabledInSite();
 
-        }, CoreSites.instance.getCurrentSiteId());
+        }, CoreSites.getCurrentSiteId());
 
         this.coursesObserver = CoreEvents.on(
             CoreCoursesProvider.EVENT_MY_COURSES_UPDATED,
@@ -83,7 +83,7 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
                 this.refreshContent();
             },
 
-            CoreSites.instance.getCurrentSiteId(),
+            CoreSites.getCurrentSiteId(),
         );
 
         super.ngOnInit();
@@ -107,17 +107,17 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
     protected async invalidateContent(): Promise<void> {
         const promises: Promise<void>[] = [];
 
-        promises.push(CoreCourses.instance.invalidateUserCourses().finally(() =>
+        promises.push(CoreCourses.invalidateUserCourses().finally(() =>
             // Invalidate course completion data.
-            CoreUtils.instance.allPromises(this.courseIds.map((courseId) =>
-                AddonCourseCompletion.instance.invalidateCourseCompletion(courseId)))));
+            CoreUtils.allPromises(this.courseIds.map((courseId) =>
+                AddonCourseCompletion.invalidateCourseCompletion(courseId)))));
 
-        promises.push(CoreCourseOptionsDelegate.instance.clearAndInvalidateCoursesOptions());
+        promises.push(CoreCourseOptionsDelegate.clearAndInvalidateCoursesOptions());
         if (this.courseIds.length > 0) {
-            promises.push(CoreCourses.instance.invalidateCoursesByField('ids', this.courseIds.join(',')));
+            promises.push(CoreCourses.invalidateCoursesByField('ids', this.courseIds.join(',')));
         }
 
-        await CoreUtils.instance.allPromises(promises).finally(() => {
+        await CoreUtils.allPromises(promises).finally(() => {
             this.prefetchIconsInitialized = false;
         });
     }
@@ -131,7 +131,7 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
         const showCategories = this.block.configsRecord && this.block.configsRecord.displaycategories &&
             this.block.configsRecord.displaycategories.value == '1';
 
-        this.courses = await CoreCoursesHelper.instance.getUserCoursesWithOptions('timemodified', 0, 'isfavourite', showCategories);
+        this.courses = await CoreCoursesHelper.getUserCoursesWithOptions('timemodified', 0, 'isfavourite', showCategories);
         this.initPrefetchCoursesIcons();
     }
 
@@ -144,7 +144,7 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
         CoreEvents.trigger(CoreCoursesProvider.EVENT_MY_COURSES_REFRESHED);
 
         try {
-            await CoreCourses.instance.invalidateUserCourses();
+            await CoreCourses.invalidateUserCourses();
         } catch (error) {
             // Ignore errors.
         }
@@ -184,7 +184,7 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
 
         this.prefetchIconsInitialized = true;
 
-        this.prefetchCoursesData = await CoreCourseHelper.instance.initPrefetchCoursesIcons(this.courses, this.prefetchCoursesData);
+        this.prefetchCoursesData = await CoreCourseHelper.initPrefetchCoursesIcons(this.courses, this.prefetchCoursesData);
     }
 
     /**
@@ -196,10 +196,10 @@ export class AddonBlockStarredCoursesComponent extends CoreBlockBaseComponent im
         const initialIcon = this.prefetchCoursesData.icon;
 
         try {
-            return CoreCourseHelper.instance.prefetchCourses(this.courses, this.prefetchCoursesData);
+            return CoreCourseHelper.prefetchCourses(this.courses, this.prefetchCoursesData);
         } catch (error) {
             if (!this.isDestroyed) {
-                CoreDomUtils.instance.showErrorModalDefault(error, 'core.course.errordownloadingcourse', true);
+                CoreDomUtils.showErrorModalDefault(error, 'core.course.errordownloadingcourse', true);
                 this.prefetchCoursesData.icon = initialIcon;
             }
         }

src/addons/block/starredcourses/services/block-handler.ts

@@ -43,4 +43,4 @@ export class AddonBlockStarredCoursesHandlerService extends CoreBlockBaseHandler
 
 }
 
-export class AddonBlockStarredCoursesHandler extends makeSingleton(AddonBlockStarredCoursesHandlerService) {}
+export const AddonBlockStarredCoursesHandler = makeSingleton(AddonBlockStarredCoursesHandlerService);

src/addons/block/starredcourses/starredcourses.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockStarredCoursesHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockStarredCoursesHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockStarredCoursesHandler.instance);
             },
         },
     ],

src/addons/block/tags/services/block-handler.ts

@@ -44,4 +44,4 @@ export class AddonBlockTagsHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockTagsHandler extends makeSingleton(AddonBlockTagsHandlerService) {}
+export const AddonBlockTagsHandler = makeSingleton(AddonBlockTagsHandlerService);

src/addons/block/tags/tags.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockTagsComponentsModule } from './components/components.module';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockTagsHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockTagsHandler.instance);
             },
         },
     ],

src/addons/block/timeline/components/events/events.ts

@@ -51,7 +51,7 @@ export class AddonBlockTimelineEventsComponent implements OnChanges {
      * Detect changes on input properties.
      */
     ngOnChanges(changes: {[name: string]: SimpleChange}): void {
-        this.showCourse = CoreUtils.instance.isTrueOrOne(this.showCourse);
+        this.showCourse = CoreUtils.isTrueOrOne(this.showCourse);
 
         if (changes.events || changes.from || changes.to) {
             if (this.events && this.events.length > 0) {
@@ -60,7 +60,7 @@ export class AddonBlockTimelineEventsComponent implements OnChanges {
 
                 const eventsByDay: Record<number, AddonCalendarEvent[]> = {};
                 filteredEvents.forEach((event) => {
-                    const dayTimestamp = CoreTimeUtils.instance.getMidnightForTimestamp(event.timesort);
+                    const dayTimestamp = CoreTimeUtils.getMidnightForTimestamp(event.timesort);
                     if (eventsByDay[dayTimestamp]) {
                         eventsByDay[dayTimestamp].push(event);
                     } else {
@@ -68,7 +68,7 @@ export class AddonBlockTimelineEventsComponent implements OnChanges {
                     }
                 });
 
-                const todaysMidnight = CoreTimeUtils.instance.getMidnightForTimestamp();
+                const todaysMidnight = CoreTimeUtils.getMidnightForTimestamp();
                 this.filteredEvents = [];
                 Object.keys(eventsByDay).forEach((key) => {
                     const dayTimestamp = parseInt(key);
@@ -102,7 +102,7 @@ export class AddonBlockTimelineEventsComponent implements OnChanges {
 
             return start <= event.timesort;
         }).map((event) => {
-            event.iconUrl = CoreCourse.instance.getModuleIconSrc(event.icon.component);
+            event.iconUrl = CoreCourse.getModuleIconSrc(event.icon.component);
 
             return event;
         });
@@ -127,14 +127,14 @@ export class AddonBlockTimelineEventsComponent implements OnChanges {
         e.stopPropagation();
 
         // Fix URL format.
-        url = CoreTextUtils.instance.decodeHTMLEntities(url);
+        url = CoreTextUtils.decodeHTMLEntities(url);
 
-        const modal = await CoreDomUtils.instance.showModalLoading();
+        const modal = await CoreDomUtils.showModalLoading();
 
         try {
-            const treated = await CoreContentLinksHelper.instance.handleLink(url);
+            const treated = await CoreContentLinksHelper.handleLink(url);
             if (!treated) {
-                return CoreSites.instance.getCurrentSite()?.openInBrowserWithAutoLoginIfSameSite(url);
+                return CoreSites.getCurrentSite()?.openInBrowserWithAutoLoginIfSameSite(url);
             }
         } finally {
             modal.dismiss();

src/addons/block/timeline/components/timeline/timeline.ts

@@ -69,7 +69,7 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
      * Component being initialized.
      */
     async ngOnInit(): Promise<void> {
-        this.currentSite = CoreSites.instance.getCurrentSite();
+        this.currentSite = CoreSites.getCurrentSite();
 
         this.filter = await this.currentSite!.getLocalSiteConfig('AddonBlockTimelineFilter', this.filter);
         this.switchFilter();
@@ -87,15 +87,15 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
     protected invalidateContent(): Promise<void> {
         const promises: Promise<void>[] = [];
 
-        promises.push(AddonBlockTimeline.instance.invalidateActionEventsByTimesort());
-        promises.push(AddonBlockTimeline.instance.invalidateActionEventsByCourses());
-        promises.push(CoreCourses.instance.invalidateUserCourses());
-        promises.push(CoreCourseOptionsDelegate.instance.clearAndInvalidateCoursesOptions());
+        promises.push(AddonBlockTimeline.invalidateActionEventsByTimesort());
+        promises.push(AddonBlockTimeline.invalidateActionEventsByCourses());
+        promises.push(CoreCourses.invalidateUserCourses());
+        promises.push(CoreCourseOptionsDelegate.clearAndInvalidateCoursesOptions());
         if (this.courseIds.length > 0) {
-            promises.push(CoreCourses.instance.invalidateCoursesByField('ids', this.courseIds.join(',')));
+            promises.push(CoreCourses.invalidateCoursesByField('ids', this.courseIds.join(',')));
         }
 
-        return CoreUtils.instance.allPromises(promises);
+        return CoreUtils.allPromises(promises);
     }
 
     /**
@@ -124,7 +124,7 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
         try {
             await this.fetchMyOverviewTimeline(this.timeline.canLoadMore);
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, this.fetchContentDefaultError);
+            CoreDomUtils.showErrorModalDefault(error, this.fetchContentDefaultError);
         }
     }
 
@@ -136,11 +136,11 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
      */
     async loadMoreCourse(course: AddonBlockTimelineCourse): Promise<void> {
         try {
-            const courseEvents = await AddonBlockTimeline.instance.getActionEventsByCourse(course.id, course.canLoadMore);
+            const courseEvents = await AddonBlockTimeline.getActionEventsByCourse(course.id, course.canLoadMore);
             course.events = course.events?.concat(courseEvents.events);
             course.canLoadMore = courseEvents.canLoadMore;
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, this.fetchContentDefaultError);
+            CoreDomUtils.showErrorModalDefault(error, this.fetchContentDefaultError);
         }
     }
 
@@ -151,7 +151,7 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
      * @return Promise resolved when done.
      */
     protected async fetchMyOverviewTimeline(afterEventId?: number): Promise<void> {
-        const events = await AddonBlockTimeline.instance.getActionEventsByTimesort(afterEventId);
+        const events = await AddonBlockTimeline.getActionEventsByTimesort(afterEventId);
 
         this.timeline.events = events.events;
         this.timeline.canLoadMore = events.canLoadMore;
@@ -163,8 +163,8 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
      * @return Promise resolved when done.
      */
     protected async fetchMyOverviewTimelineByCourses(): Promise<void> {
-        const courses = await CoreCoursesHelper.instance.getUserCoursesWithOptions();
-        const today = CoreTimeUtils.instance.timestamp();
+        const courses = await CoreCoursesHelper.getUserCoursesWithOptions();
+        const today = CoreTimeUtils.timestamp();
 
         this.timelineCourses.courses = courses.filter((course) =>
             (course.startdate || 0) <= today && (!course.enddate || course.enddate >= today));
@@ -172,7 +172,7 @@ export class AddonBlockTimelineComponent extends CoreBlockBaseComponent implemen
         if (this.timelineCourses.courses.length > 0) {
             this.courseIds = this.timelineCourses.courses.map((course) => course.id);
 
-            const courseEvents = await AddonBlockTimeline.instance.getActionEventsByCourses(this.courseIds);
+            const courseEvents = await AddonBlockTimeline.getActionEventsByCourses(this.courseIds);
 
             this.timelineCourses.courses.forEach((course) => {
                 course.events = courseEvents[course.id].events;

src/addons/block/timeline/services/block-handler.ts

@@ -36,11 +36,11 @@ export class AddonBlockTimelineHandlerService extends CoreBlockBaseHandler {
      * @return Whether or not the handler is enabled on a site level.
      */
     async isEnabled(): Promise<boolean> {
-        const enabled = await AddonBlockTimeline.instance.isAvailable();
-        const currentSite = CoreSites.instance.getCurrentSite();
+        const enabled = await AddonBlockTimeline.isAvailable();
+        const currentSite = CoreSites.getCurrentSite();
 
         return enabled && ((currentSite && currentSite.isVersionGreaterEqualThan('3.6')) ||
-            !CoreCourses.instance.isMyCoursesDisabledInSite());
+            !CoreCourses.isMyCoursesDisabledInSite());
     }
 
     /**
@@ -59,4 +59,4 @@ export class AddonBlockTimelineHandlerService extends CoreBlockBaseHandler {
 
 }
 
-export class AddonBlockTimelineHandler extends makeSingleton(AddonBlockTimelineHandlerService) {}
+export const AddonBlockTimelineHandler = makeSingleton(AddonBlockTimelineHandlerService);

src/addons/block/timeline/services/timeline.ts

@@ -53,7 +53,7 @@ export class AddonBlockTimelineProvider {
         afterEventId?: number,
         siteId?: string,
     ): Promise<{ events: AddonCalendarEvent[]; canLoadMore?: number }> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const time = moment().subtract(14, 'days').unix(); // Check two weeks ago.
 
@@ -104,7 +104,7 @@ export class AddonBlockTimelineProvider {
         courseIds: number[],
         siteId?: string,
     ): Promise<{[courseId: string]: { events: AddonCalendarEvent[]; canLoadMore: number } }> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const time = moment().subtract(14, 'days').unix(); // Check two weeks ago.
 
@@ -156,7 +156,7 @@ export class AddonBlockTimelineProvider {
         afterEventId?: number,
         siteId?: string,
     ): Promise<{ events: AddonCalendarEvent[]; canLoadMore?: number }> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const timesortfrom = moment().subtract(14, 'days').unix(); // Check two weeks ago.
         const limitnum = AddonBlockTimelineProvider.EVENTS_LIMIT;
@@ -226,7 +226,7 @@ export class AddonBlockTimelineProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateActionEventsByCourses(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getActionEventsByCoursesCacheKey());
     }
@@ -238,7 +238,7 @@ export class AddonBlockTimelineProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateActionEventsByTimesort(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getActionEventsByTimesortPrefixCacheKey());
     }
@@ -250,10 +250,10 @@ export class AddonBlockTimelineProvider {
      * @return Promise resolved with true if available, resolved with false or rejected otherwise.
      */
     async isAvailable(siteId?: string): Promise<boolean> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         // First check if dashboard is disabled.
-        if (CoreCoursesDashboard.instance.isDisabledInSite(site)) {
+        if (CoreCoursesDashboard.isDisabledInSite(site)) {
             return false;
         }
 
@@ -287,4 +287,4 @@ export class AddonBlockTimelineProvider {
 
 }
 
-export class AddonBlockTimeline extends makeSingleton(AddonBlockTimelineProvider) {}
+export const AddonBlockTimeline = makeSingleton(AddonBlockTimelineProvider);

src/addons/block/timeline/timeline.module.ts

@@ -30,7 +30,7 @@ import { AddonBlockTimelineHandler } from './services/block-handler';
             provide: APP_INITIALIZER,
             multi: true,
             useValue: () => {
-                CoreBlockDelegate.instance.registerHandler(AddonBlockTimelineHandler.instance);
+                CoreBlockDelegate.registerHandler(AddonBlockTimelineHandler.instance);
             },
         },
     ],

src/addons/calendar/calendar.module.ts

@@ -55,13 +55,13 @@ const mainMenuChildrenRoutes: Routes = [
             multi: true,
             deps: [],
             useFactory: () => async () => {
-                CoreContentLinksDelegate.instance.registerHandler(AddonCalendarViewLinkHandler.instance);
-                CoreMainMenuDelegate.instance.registerHandler(AddonCalendarMainMenuHandler.instance);
-                CoreCronDelegate.instance.register(AddonCalendarSyncCronHandler.instance);
+                CoreContentLinksDelegate.registerHandler(AddonCalendarViewLinkHandler.instance);
+                CoreMainMenuDelegate.registerHandler(AddonCalendarMainMenuHandler.instance);
+                CoreCronDelegate.register(AddonCalendarSyncCronHandler.instance);
 
-                await AddonCalendar.instance.initialize();
+                await AddonCalendar.initialize();
 
-                AddonCalendar.instance.scheduleAllSitesEventsNotifications();
+                AddonCalendar.scheduleAllSitesEventsNotifications();
             },
         },
     ],

src/addons/calendar/components/calendar/calendar.ts

@@ -89,14 +89,14 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         differs: KeyValueDiffers,
     ) {
 
-        this.currentSiteId = CoreSites.instance.getCurrentSiteId();
+        this.currentSiteId = CoreSites.getCurrentSiteId();
 
-        if (CoreLocalNotifications.instance.isAvailable()) {
+        if (CoreLocalNotifications.isAvailable()) {
             // Re-schedule events if default time changes.
             this.obsDefaultTimeChange = CoreEvents.on(AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_CHANGED, () => {
                 this.weeks.forEach((week) => {
                     week.days.forEach((day) => {
-                        AddonCalendar.instance.scheduleEventsNotifications(day.eventsFormated!);
+                        AddonCalendar.scheduleEventsNotifications(day.eventsFormated!);
                     });
                 });
             }, this.currentSiteId);
@@ -144,9 +144,9 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
      * Detect and act upon changes that Angular can’t or won’t detect on its own (objects and arrays).
      */
     ngDoCheck(): void {
-        this.canNavigate = typeof this.canNavigate == 'undefined' ? true : CoreUtils.instance.isTrueOrOne(this.canNavigate);
+        this.canNavigate = typeof this.canNavigate == 'undefined' ? true : CoreUtils.isTrueOrOne(this.canNavigate);
         this.displayNavButtons = typeof this.displayNavButtons == 'undefined' ? true :
-            CoreUtils.instance.isTrueOrOne(this.displayNavButtons);
+            CoreUtils.isTrueOrOne(this.displayNavButtons);
 
         if (this.weeks) {
             // Check if there's any change in the filter object.
@@ -168,9 +168,9 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         promises.push(this.loadCategories());
 
         // Get offline events.
-        promises.push(AddonCalendarOffline.instance.getAllEditedEvents().then((events) => {
+        promises.push(AddonCalendarOffline.getAllEditedEvents().then((events) => {
             // Classify them by month.
-            this.offlineEvents = AddonCalendarHelper.instance.classifyIntoMonths(events);
+            this.offlineEvents = AddonCalendarHelper.classifyIntoMonths(events);
 
             // Get the IDs of events edited in offline.
             const filtered = events.filter((event) => event.id! > 0);
@@ -180,14 +180,14 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         }));
 
         // Get events deleted in offline.
-        promises.push(AddonCalendarOffline.instance.getAllDeletedEventsIds().then((ids) => {
+        promises.push(AddonCalendarOffline.getAllDeletedEventsIds().then((ids) => {
             this.deletedEvents = ids;
 
             return;
         }));
 
         // Get time format to use.
-        promises.push(AddonCalendar.instance.getCalendarTimeFormat().then((value) => {
+        promises.push(AddonCalendar.getCalendarTimeFormat().then((value) => {
             this.timeFormat = value;
 
             return;
@@ -199,7 +199,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
             await this.fetchEvents();
 
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
         }
 
         this.loaded = true;
@@ -214,22 +214,22 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         // Don't pass courseId and categoryId, we'll filter them locally.
         let result: { daynames: Partial<AddonCalendarDayName>[]; weeks: Partial<AddonCalendarWeek>[] };
         try {
-            result = await AddonCalendar.instance.getMonthlyEvents(this.year!, this.month!);
+            result = await AddonCalendar.getMonthlyEvents(this.year!, this.month!);
         } catch (error) {
-            if (!CoreApp.instance.isOnline()) {
+            if (!CoreApp.isOnline()) {
                 // Allow navigating to non-cached months in offline (behave as if using emergency cache).
-                result = await AddonCalendarHelper.instance.getOfflineMonthWeeks(this.year!, this.month!);
+                result = await AddonCalendarHelper.getOfflineMonthWeeks(this.year!, this.month!);
             } else {
                 throw error;
             }
         }
 
         // Calculate the period name. We don't use the one in result because it's in server's language.
-        this.periodName = CoreTimeUtils.instance.userDate(
+        this.periodName = CoreTimeUtils.userDate(
             new Date(this.year!, this.month! - 1).getTime(),
             'core.strftimemonthyear',
         );
-        this.weekDays = AddonCalendar.instance.getWeekDays(result.daynames[0].dayno);
+        this.weekDays = AddonCalendar.getWeekDays(result.daynames[0].dayno);
         this.weeks = result.weeks as AddonCalendarWeek[];
         this.calculateIsCurrentMonth();
 
@@ -239,7 +239,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
                 day.filteredEvents = day.filteredEvents || [];
                 day.events.forEach((event) => {
                     /// Format online events.
-                    day.eventsFormated!.push(AddonCalendarHelper.instance.formatEventData(event));
+                    day.eventsFormated!.push(AddonCalendarHelper.formatEventData(event));
                 });
             });
         });
@@ -280,7 +280,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         }
 
         try {
-            const cats = await CoreCourses.instance.getCategories(0, true);
+            const cats = await CoreCourses.getCategories(0, true);
             this.categoriesRetrieved = true;
             this.categories = {};
 
@@ -299,14 +299,14 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
     filterEvents(): void {
         this.weeks.forEach((week) => {
             week.days.forEach((day) => {
-                day.filteredEvents = AddonCalendarHelper.instance.getFilteredEvents(
+                day.filteredEvents = AddonCalendarHelper.getFilteredEvents(
                     day.eventsFormated!,
                     this.filter!,
                     this.categories,
                 );
 
                 // Re-calculate some properties.
-                AddonCalendarHelper.instance.calculateDayData(day, day.filteredEvents);
+                AddonCalendarHelper.calculateDayData(day, day.filteredEvents);
             });
         });
     }
@@ -322,10 +322,10 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
 
         // Don't invalidate monthly events after a change, it has already been handled.
         if (!afterChange) {
-            promises.push(AddonCalendar.instance.invalidateMonthlyEvents(this.year!, this.month!));
+            promises.push(AddonCalendar.invalidateMonthlyEvents(this.year!, this.month!));
         }
-        promises.push(CoreCourses.instance.invalidateCategories(0, true));
-        promises.push(AddonCalendar.instance.invalidateTimeFormat());
+        promises.push(CoreCourses.invalidateCategories(0, true));
+        promises.push(AddonCalendar.invalidateTimeFormat());
 
         this.categoriesRetrieved = false; // Get categories again.
 
@@ -345,7 +345,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         try {
             await this.fetchEvents();
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
             this.decreaseMonth();
         }
         this.loaded = true;
@@ -362,7 +362,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
         try {
             await this.fetchEvents();
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
             this.increaseMonth();
         }
         this.loaded = true;
@@ -394,7 +394,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
     calculateIsCurrentMonth(): void {
         const now = new Date();
 
-        this.currentTime = CoreTimeUtils.instance.timestamp();
+        this.currentTime = CoreTimeUtils.timestamp();
 
         this.isCurrentMonth = this.year == now.getFullYear() && this.month == now.getMonth() + 1;
         this.isPastMonth = this.year! < now.getFullYear() || (this.year == now.getFullYear() && this.month! < now.getMonth() + 1);
@@ -417,7 +417,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
             await this.fetchEvents();
             this.isCurrentMonth = true;
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
             this.year = initialYear;
             this.month = initialMonth;
         }
@@ -454,13 +454,13 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
      */
     protected mergeEvents(): void {
         const monthOfflineEvents: { [day: number]: AddonCalendarEventToDisplay[] } =
-            this.offlineEvents[AddonCalendarHelper.instance.getMonthId(this.year!, this.month!)];
+            this.offlineEvents[AddonCalendarHelper.getMonthId(this.year!, this.month!)];
 
         this.weeks.forEach((week) => {
             week.days.forEach((day) => {
 
                 // Schedule notifications for the events retrieved (only future events will be scheduled).
-                AddonCalendar.instance.scheduleEventsNotifications(day.eventsFormated!);
+                AddonCalendar.scheduleEventsNotifications(day.eventsFormated!);
 
                 if (monthOfflineEvents || this.deletedEvents.length) {
                     // There is offline data, merge it.
@@ -480,7 +480,7 @@ export class AddonCalendarCalendarComponent implements OnInit, DoCheck, OnDestro
                     if (monthOfflineEvents && monthOfflineEvents[day.mday]) {
                         // Add the offline events (either new or edited).
                         day.eventsFormated =
-                            AddonCalendarHelper.instance.sortEvents(day.eventsFormated!.concat(monthOfflineEvents[day.mday]));
+                            AddonCalendarHelper.sortEvents(day.eventsFormated!.concat(monthOfflineEvents[day.mday]));
                     }
                 }
             });

src/addons/calendar/components/filter/filter.ts

@@ -48,7 +48,7 @@ export class AddonCalendarFilterPopoverComponent implements OnInit {
     types: string[] = [];
 
     constructor() {
-        CoreUtils.instance.enumKeys(AddonCalendarEventType).forEach((name) => {
+        CoreUtils.enumKeys(AddonCalendarEventType).forEach((name) => {
             const value = AddonCalendarEventType[name];
             this.typeIcons[value] = AddonCalendarEventIcons[name];
             this.types.push(value);

src/addons/calendar/components/upcoming-events/upcoming-events.ts

@@ -64,11 +64,11 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
     constructor(
         differs: KeyValueDiffers,
     ) {
-        this.currentSiteId = CoreSites.instance.getCurrentSiteId();
+        this.currentSiteId = CoreSites.getCurrentSiteId();
 
-        if (CoreLocalNotifications.instance.isAvailable()) {            // Re-schedule events if default time changes.
+        if (CoreLocalNotifications.isAvailable()) {            // Re-schedule events if default time changes.
             this.obsDefaultTimeChange = CoreEvents.on(AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_CHANGED, () => {
-                AddonCalendar.instance.scheduleEventsNotifications(this.onlineEvents);
+                AddonCalendar.scheduleEventsNotifications(this.onlineEvents);
             }, this.currentSiteId);
         }
 
@@ -124,31 +124,31 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
         promises.push(this.loadCategories());
 
         // Get offline events.
-        promises.push(AddonCalendarOffline.instance.getAllEditedEvents().then((offlineEvents) => {
+        promises.push(AddonCalendarOffline.getAllEditedEvents().then((offlineEvents) => {
             // Format data.
             const events: AddonCalendarEventToDisplay[] = offlineEvents.map((event) =>
-                AddonCalendarHelper.instance.formatOfflineEventData(event));
+                AddonCalendarHelper.formatOfflineEventData(event));
 
-            this.offlineEvents = AddonCalendarHelper.instance.sortEvents(events);
+            this.offlineEvents = AddonCalendarHelper.sortEvents(events);
 
             return;
         }));
 
         // Get events deleted in offline.
-        promises.push(AddonCalendarOffline.instance.getAllDeletedEventsIds().then((ids) => {
+        promises.push(AddonCalendarOffline.getAllDeletedEventsIds().then((ids) => {
             this.deletedEvents = ids;
 
             return;
         }));
 
         // Get user preferences.
-        promises.push(AddonCalendar.instance.getCalendarLookAhead().then((value) => {
+        promises.push(AddonCalendar.getCalendarLookAhead().then((value) => {
             this.lookAhead = value;
 
             return;
         }));
 
-        promises.push(AddonCalendar.instance.getCalendarTimeFormat().then((value) => {
+        promises.push(AddonCalendar.getCalendarTimeFormat().then((value) => {
             this.timeFormat = value;
 
             return;
@@ -160,7 +160,7 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
             this.fetchEvents();
 
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
         }
 
         this.loaded = true;
@@ -173,10 +173,10 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
      */
     async fetchEvents(): Promise<void> {
         // Don't pass courseId and categoryId, we'll filter them locally.
-        const result = await AddonCalendar.instance.getUpcomingEvents();
-        this.onlineEvents = result.events.map((event) => AddonCalendarHelper.instance.formatEventData(event));
+        const result = await AddonCalendar.getUpcomingEvents();
+        this.onlineEvents = result.events.map((event) => AddonCalendarHelper.formatEventData(event));
         // Schedule notifications for the events retrieved.
-        AddonCalendar.instance.scheduleEventsNotifications(this.onlineEvents);
+        AddonCalendar.scheduleEventsNotifications(this.onlineEvents);
         // Merge the online events with offline data.
         this.events = this.mergeEvents();
         // Filter events by course.
@@ -184,7 +184,7 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
 
         // Re-calculate the formatted time so it uses the device date.
         const promises = this.events.map((event) =>
-            AddonCalendar.instance.formatEventTime(event, this.timeFormat!).then((time) => {
+            AddonCalendar.formatEventTime(event, this.timeFormat!).then((time) => {
                 event.formattedtime = time;
 
                 return;
@@ -205,7 +205,7 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
         }
 
         try {
-            const cats = await CoreCourses.instance.getCategories(0, true);
+            const cats = await CoreCourses.getCategories(0, true);
             this.categoriesRetrieved = true;
             this.categories = {};
 
@@ -222,7 +222,7 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
      * Filter events based on the filter popover.
      */
     protected filterEvents(): void {
-        this.filteredEvents = AddonCalendarHelper.instance.getFilteredEvents(this.events, this.filter!, this.categories);
+        this.filteredEvents = AddonCalendarHelper.getFilteredEvents(this.events, this.filter!, this.categories);
     }
 
     /**
@@ -236,11 +236,11 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
 
         // Don't invalidate upcoming events after a change, it has already been handled.
         if (!afterChange) {
-            promises.push(AddonCalendar.instance.invalidateAllUpcomingEvents());
+            promises.push(AddonCalendar.invalidateAllUpcomingEvents());
         }
-        promises.push(CoreCourses.instance.invalidateCategories(0, true));
-        promises.push(AddonCalendar.instance.invalidateLookAhead());
-        promises.push(AddonCalendar.instance.invalidateTimeFormat());
+        promises.push(CoreCourses.invalidateCategories(0, true));
+        promises.push(AddonCalendar.invalidateLookAhead());
+        promises.push(AddonCalendar.invalidateTimeFormat());
 
         this.categoriesRetrieved = false; // Get categories again.
 
@@ -297,7 +297,7 @@ export class AddonCalendarUpcomingEventsComponent implements OnInit, DoCheck, On
         // Merge both arrays and sort them.
         result = result.concat(periodOfflineEvents);
 
-        return AddonCalendarHelper.instance.sortEvents(result);
+        return AddonCalendarHelper.sortEvents(result);
     }
 
     /**

src/addons/calendar/pages/day/day.page.ts

@@ -102,12 +102,12 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
     };
 
     constructor() {
-        this.currentSiteId = CoreSites.instance.getCurrentSiteId();
+        this.currentSiteId = CoreSites.getCurrentSiteId();
 
-        if (CoreLocalNotifications.instance.isAvailable()) {
+        if (CoreLocalNotifications.isAvailable()) {
             // Re-schedule events if default time changes.
             this.obsDefaultTimeChange = CoreEvents.on(AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_CHANGED, () => {
-                AddonCalendar.instance.scheduleEventsNotifications(this.onlineEvents);
+                AddonCalendar.scheduleEventsNotifications(this.onlineEvents);
             }, this.currentSiteId);
         }
 
@@ -210,17 +210,17 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
                 this.filter = data;
 
                 // Course viewed has changed, check if the user can create events for this course calendar.
-                this.canCreate = await AddonCalendarHelper.instance.canEditEvents(this.filter.courseId);
+                this.canCreate = await AddonCalendarHelper.canEditEvents(this.filter.courseId);
 
                 this.filterEvents();
             },
         );
 
         // Refresh online status when changes.
-        this.onlineObserver = Network.instance.onChange().subscribe(() => {
+        this.onlineObserver = Network.onChange().subscribe(() => {
             // Execute the callback in the Angular zone, so change detection doesn't stop working.
-            NgZone.instance.run(() => {
-                this.isOnline = CoreApp.instance.isOnline();
+            NgZone.run(() => {
+                this.isOnline = CoreApp.isOnline();
             });
         });
     }
@@ -231,20 +231,20 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
     ngOnInit(): void {
         const types: string[] = [];
 
-        CoreUtils.instance.enumKeys(AddonCalendarEventType).forEach((name) => {
+        CoreUtils.enumKeys(AddonCalendarEventType).forEach((name) => {
             const value = AddonCalendarEventType[name];
-            this.filter[name] = CoreNavigator.instance.getRouteBooleanParam(name) ?? true;
+            this.filter[name] = CoreNavigator.getRouteBooleanParam(name) ?? true;
             types.push(value);
         });
-        this.filter.courseId = CoreNavigator.instance.getRouteNumberParam('courseId') || -1;
-        this.filter.categoryId = CoreNavigator.instance.getRouteNumberParam('categoryId');
+        this.filter.courseId = CoreNavigator.getRouteNumberParam('courseId') || -1;
+        this.filter.categoryId = CoreNavigator.getRouteNumberParam('categoryId');
 
         this.filter.filtered = typeof this.filter.courseId != 'undefined' || types.some((name) => !this.filter[name]);
 
         const now = new Date();
-        this.year = CoreNavigator.instance.getRouteNumberParam('year') || now.getFullYear();
-        this.month = CoreNavigator.instance.getRouteNumberParam('month') || (now.getMonth() + 1);
-        this.day = CoreNavigator.instance.getRouteNumberParam('day') || now.getDate();
+        this.year = CoreNavigator.getRouteNumberParam('year') || now.getFullYear();
+        this.month = CoreNavigator.getRouteNumberParam('month') || (now.getMonth() + 1);
+        this.day = CoreNavigator.getRouteNumberParam('day') || now.getDate();
 
         this.calculateCurrentMoment();
         this.calculateIsCurrentDay();
@@ -262,7 +262,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
     async fetchData(sync?: boolean): Promise<void> {
 
         this.syncIcon = CoreConstants.ICON_LOADING;
-        this.isOnline = CoreApp.instance.isOnline();
+        this.isOnline = CoreApp.isOnline();
 
         if (sync) {
             await this.sync();
@@ -272,7 +272,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             const promises: Promise<void>[] = [];
 
             // Load courses for the popover.
-            promises.push(CoreCoursesHelper.instance.getCoursesForPopover(this.filter.courseId).then((data) => {
+            promises.push(CoreCoursesHelper.getCoursesForPopover(this.filter.courseId).then((data) => {
                 this.courses = data.courses;
 
                 return;
@@ -282,9 +282,9 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             promises.push(this.loadCategories());
 
             // Get offline events.
-            promises.push(AddonCalendarOffline.instance.getAllEditedEvents().then((offlineEvents) => {
+            promises.push(AddonCalendarOffline.getAllEditedEvents().then((offlineEvents) => {
                 // Classify them by month & day.
-                this.offlineEvents = AddonCalendarHelper.instance.classifyIntoMonths(offlineEvents);
+                this.offlineEvents = AddonCalendarHelper.classifyIntoMonths(offlineEvents);
 
                 // Get the IDs of events edited in offline.
                 this.offlineEditedEventsIds = offlineEvents.filter((event) => event.id! > 0).map((event) => event.id!);
@@ -293,21 +293,21 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             }));
 
             // Get events deleted in offline.
-            promises.push(AddonCalendarOffline.instance.getAllDeletedEventsIds().then((ids) => {
+            promises.push(AddonCalendarOffline.getAllDeletedEventsIds().then((ids) => {
                 this.deletedEvents = ids;
 
                 return;
             }));
 
             // Check if user can create events.
-            promises.push(AddonCalendarHelper.instance.canEditEvents(this.filter.courseId).then((canEdit) => {
+            promises.push(AddonCalendarHelper.canEditEvents(this.filter.courseId).then((canEdit) => {
                 this.canCreate = canEdit;
 
                 return;
             }));
 
             // Get user preferences.
-            promises.push(AddonCalendar.instance.getCalendarTimeFormat().then((value) => {
+            promises.push(AddonCalendar.getCalendarTimeFormat().then((value) => {
                 this.timeFormat = value;
 
                 return;
@@ -317,7 +317,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
 
             await this.fetchEvents();
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
         }
 
         this.loaded = true;
@@ -333,10 +333,10 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
         let result: AddonCalendarCalendarDay;
         try {
             // Don't pass courseId and categoryId, we'll filter them locally.
-            result = await AddonCalendar.instance.getDayEvents(this.year, this.month, this.day);
-            this.onlineEvents = result.events.map((event) => AddonCalendarHelper.instance.formatEventData(event));
+            result = await AddonCalendar.getDayEvents(this.year, this.month, this.day);
+            this.onlineEvents = result.events.map((event) => AddonCalendarHelper.formatEventData(event));
         } catch (error) {
-            if (CoreApp.instance.isOnline()) {
+            if (CoreApp.isOnline()) {
                 throw error;
             }
             // Allow navigating to non-cached days in offline (behave as if using emergency cache).
@@ -344,13 +344,13 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
         }
 
         // Calculate the period name. We don't use the one in result because it's in server's language.
-        this.periodName = CoreTimeUtils.instance.userDate(
+        this.periodName = CoreTimeUtils.userDate(
             new Date(this.year, this.month - 1, this.day).getTime(),
             'core.strftimedaydate',
         );
 
         // Schedule notifications for the events retrieved (only future events will be scheduled).
-        AddonCalendar.instance.scheduleEventsNotifications(this.onlineEvents);
+        AddonCalendar.scheduleEventsNotifications(this.onlineEvents);
         // Merge the online events with offline data.
         this.events = this.mergeEvents();
         // Filter events by course.
@@ -362,7 +362,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
         const promises = this.events.map((event) => {
             event.ispast = this.isPastDay || (this.isCurrentDay && this.isEventPast(event));
 
-            return AddonCalendar.instance.formatEventTime(event, this.timeFormat!, true, dayTime).then((time) => {
+            return AddonCalendar.formatEventTime(event, this.timeFormat!, true, dayTime).then((time) => {
                 event.formattedtime = time;
 
                 return;
@@ -385,7 +385,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             return this.onlineEvents;
         }
 
-        const monthOfflineEvents = this.offlineEvents[AddonCalendarHelper.instance.getMonthId(this.year, this.month)];
+        const monthOfflineEvents = this.offlineEvents[AddonCalendarHelper.getMonthId(this.year, this.month)];
         const dayOfflineEvents = monthOfflineEvents && monthOfflineEvents[this.day];
         let result = this.onlineEvents;
 
@@ -412,7 +412,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
         if (dayOfflineEvents && dayOfflineEvents.length) {
             // Add the offline events (either new or edited).
             this.hasOffline = true;
-            result = AddonCalendarHelper.instance.sortEvents(result.concat(dayOfflineEvents));
+            result = AddonCalendarHelper.sortEvents(result.concat(dayOfflineEvents));
         }
 
         return result;
@@ -422,7 +422,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
      * Filter events based on the filter popover.
      */
     protected filterEvents(): void {
-        this.filteredEvents = AddonCalendarHelper.instance.getFilteredEvents(this.events, this.filter, this.categories);
+        this.filteredEvents = AddonCalendarHelper.getFilteredEvents(this.events, this.filter, this.categories);
     }
 
     /**
@@ -457,11 +457,11 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
 
         // Don't invalidate day events after a change, it has already been handled.
         if (!afterChange) {
-            promises.push(AddonCalendar.instance.invalidateDayEvents(this.year, this.month, this.day));
+            promises.push(AddonCalendar.invalidateDayEvents(this.year, this.month, this.day));
         }
-        promises.push(AddonCalendar.instance.invalidateAllowedEventTypes());
-        promises.push(CoreCourses.instance.invalidateCategories(0, true));
-        promises.push(AddonCalendar.instance.invalidateTimeFormat());
+        promises.push(AddonCalendar.invalidateAllowedEventTypes());
+        promises.push(CoreCourses.invalidateCategories(0, true));
+        promises.push(AddonCalendar.invalidateTimeFormat());
 
         await Promise.all(promises).finally(() =>
             this.fetchData(sync));
@@ -474,7 +474,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
      */
     protected async loadCategories(): Promise<void> {
         try {
-            const cats = await CoreCourses.instance.getCategories(0, true);
+            const cats = await CoreCourses.getCategories(0, true);
             this.categories = {};
 
             // Index categories by ID.
@@ -494,10 +494,10 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
      */
     protected async sync(showErrors?: boolean): Promise<void> {
         try {
-            const result = await AddonCalendarSync.instance.syncEvents();
+            const result = await AddonCalendarSync.syncEvents();
 
             if (result.warnings && result.warnings.length) {
-                CoreDomUtils.instance.showErrorModal(result.warnings[0]);
+                CoreDomUtils.showErrorModal(result.warnings[0]);
             }
 
             if (result.updated) {
@@ -511,7 +511,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             }
         } catch (error) {
             if (showErrors) {
-                CoreDomUtils.instance.showErrorModalDefault(error, 'core.errorsync', true);
+                CoreDomUtils.showErrorModalDefault(error, 'core.errorsync', true);
             }
         }
     }
@@ -526,7 +526,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             // It's an offline event, go to the edit page.
             this.openEdit(eventId);
         } else {
-            CoreNavigator.instance.navigateToSitePath('/calendar/event', { params: { id: eventId } });
+            CoreNavigator.navigateToSitePath('/calendar/event', { params: { id: eventId } });
         }
     }
 
@@ -536,7 +536,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
      * @param event Event.
      */
     async openFilter(event: MouseEvent): Promise<void> {
-        const popover = await PopoverController.instance.create({
+        const popover = await PopoverController.create({
             component: AddonCalendarFilterPopoverComponent,
             componentProps: {
                 courses: this.courses,
@@ -566,7 +566,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
             params.courseId = this.filter.courseId;
         }
 
-        CoreNavigator.instance.navigateToSitePath('/calendar/edit', { params });
+        CoreNavigator.navigateToSitePath('/calendar/edit', { params });
     }
 
     /**
@@ -582,7 +582,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
     calculateIsCurrentDay(): void {
         const now = new Date();
 
-        this.currentTime = CoreTimeUtils.instance.timestamp();
+        this.currentTime = CoreTimeUtils.timestamp();
 
         this.isCurrentDay = this.year == now.getFullYear() && this.month == now.getMonth() + 1 && this.day == now.getDate();
         this.isPastDay = this.year < now.getFullYear() || (this.year == now.getFullYear() && this.month < now.getMonth()) ||
@@ -610,7 +610,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
 
             this.isCurrentDay = true;
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
 
             this.year = initialYear;
             this.month = initialMonth;
@@ -632,7 +632,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
         try {
             await this.fetchEvents();
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
             this.decreaseDay();
         }
         this.loaded = true;
@@ -649,7 +649,7 @@ export class AddonCalendarDayPage implements OnInit, OnDestroy {
         try {
             await this.fetchEvents();
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
             this.increaseDay();
         }
         this.loaded = true;

src/addons/calendar/pages/edit-event/edit-event.page.ts

@@ -94,13 +94,13 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
         @Optional() protected svComponent: CoreSplitViewComponent,
     ) {
 
-        this.currentSite = CoreSites.instance.getCurrentSite()!;
+        this.currentSite = CoreSites.getCurrentSite()!;
         this.errors = {
-            required: Translate.instance.instant('core.required'),
+            required: Translate.instant('core.required'),
         };
 
         // Calculate format to use. ion-datetime doesn't support escaping characters ([]), so we remove them.
-        this.dateFormat = CoreTimeUtils.instance.convertPHPToMoment(Translate.instance.instant('core.strftimedatetimeshort'))
+        this.dateFormat = CoreTimeUtils.convertPHPToMoment(Translate.instant('core.strftimedatetimeshort'))
             .replace(/[[\]]/g, '');
 
         this.form = new FormGroup({});
@@ -127,18 +127,18 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
      * Component being initialized.
      */
     ngOnInit(): void {
-        this.eventId = CoreNavigator.instance.getRouteNumberParam('eventId');
-        this.courseId = CoreNavigator.instance.getRouteNumberParam('courseId') || 0;
+        this.eventId = CoreNavigator.getRouteNumberParam('eventId');
+        this.courseId = CoreNavigator.getRouteNumberParam('courseId') || 0;
         this.title = this.eventId ? 'addon.calendar.editevent' : 'addon.calendar.newevent';
 
-        const timestamp = CoreNavigator.instance.getRouteNumberParam('timestamp');
-        const currentDate = CoreTimeUtils.instance.toDatetimeFormat(timestamp);
+        const timestamp = CoreNavigator.getRouteNumberParam('timestamp');
+        const currentDate = CoreTimeUtils.toDatetimeFormat(timestamp);
         this.form.addControl('timestart', this.fb.control(currentDate, Validators.required));
         this.form.addControl('timedurationuntil', this.fb.control(currentDate));
         this.form.addControl('courseid', this.fb.control(this.courseId));
 
         this.fetchData().finally(() => {
-            this.originalData = CoreUtils.instance.clone(this.form.value);
+            this.originalData = CoreUtils.clone(this.form.value);
             this.loaded = true;
         });
     }
@@ -156,29 +156,29 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
         // Get access info.
         try {
-            accessInfo = await AddonCalendar.instance.getAccessInformation(this.courseId);
-            this.types = await AddonCalendar.instance.getAllowedEventTypes(this.courseId);
+            accessInfo = await AddonCalendar.getAccessInformation(this.courseId);
+            this.types = await AddonCalendar.getAllowedEventTypes(this.courseId);
 
             const promises: Promise<void>[] = [];
-            const eventTypes = AddonCalendarHelper.instance.getEventTypeOptions(this.types);
+            const eventTypes = AddonCalendarHelper.getEventTypeOptions(this.types);
 
             if (!eventTypes.length) {
-                throw new CoreError(Translate.instance.instant('addon.calendar.nopermissiontoupdatecalendar'));
+                throw new CoreError(Translate.instant('addon.calendar.nopermissiontoupdatecalendar'));
             }
 
             if (this.eventId && !this.gotEventData) {
                 // Editing an event, get the event data. Wait for sync first.
-                promises.push(AddonCalendarSync.instance.waitForSync(AddonCalendarSyncProvider.SYNC_ID).then(async () => {
+                promises.push(AddonCalendarSync.waitForSync(AddonCalendarSyncProvider.SYNC_ID).then(async () => {
                     // Do not block if the scope is already destroyed.
                     if (!this.isDestroyed && this.eventId) {
-                        CoreSync.instance.blockOperation(AddonCalendarProvider.COMPONENT, this.eventId);
+                        CoreSync.blockOperation(AddonCalendarProvider.COMPONENT, this.eventId);
                     }
 
                     let eventForm: AddonCalendarEvent | AddonCalendarOfflineEventDBRecord | undefined;
 
                     // Get the event offline data if there's any.
                     try {
-                        eventForm = await AddonCalendarOffline.instance.getEvent(this.eventId!);
+                        eventForm = await AddonCalendarOffline.getEvent(this.eventId!);
 
                         this.hasOffline = true;
                     } catch {
@@ -188,7 +188,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
                     if (this.eventId! > 0) {
                         // It's an online event. get its data from server.
-                        const event = await AddonCalendar.instance.getEventById(this.eventId!);
+                        const event = await AddonCalendar.getEventById(this.eventId!);
 
                         if (!eventForm) {
                             eventForm = event; // Use offline data first.
@@ -217,7 +217,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
                 promises.push(this.fetchCategories());
             }
 
-            this.showAll = CoreUtils.instance.isTrueOrOne(this.currentSite.getStoredConfig('calendar_adminseesall')) &&
+            this.showAll = CoreUtils.isTrueOrOne(this.currentSite.getStoredConfig('calendar_adminseesall')) &&
                 accessInfo.canmanageentries;
 
             if (this.types.course || this.types.groups) {
@@ -236,18 +236,18 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
             this.eventTypes = eventTypes;
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'Error getting data.');
+            CoreDomUtils.showErrorModalDefault(error, 'Error getting data.');
             this.error = true;
         }
     }
 
     protected async fetchCategories(): Promise<void> {
-        this.categories = await CoreCourses.instance.getCategories(0, true);
+        this.categories = await CoreCourses.getCategories(0, true);
     }
 
     protected async fetchCourses(): Promise<void> {
         // Get the courses.
-        let courses = await (this.showAll ? CoreCourses.instance.getCoursesByField() : CoreCourses.instance.getUserCourses());
+        let courses = await (this.showAll ? CoreCourses.getCoursesByField() : CoreCourses.getUserCourses());
 
         if (courses.length < 0) {
             this.courses = [];
@@ -256,7 +256,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
         }
 
         const courseFillterFullname = (course: CoreCourseSearchedData | CoreEnrolledCourseData): Promise<void> =>
-            CoreFilterHelper.instance.getFiltersAndFormatText(course.fullname, 'course', course.id)
+            CoreFilterHelper.getFiltersAndFormatText(course.fullname, 'course', course.id)
                 .then((result) => {
                     course.fullname = result.text;
 
@@ -268,7 +268,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
         if (this.showAll) {
             // Remove site home from the list of courses.
-            const siteHomeId = CoreSites.instance.getCurrentSiteHomeId();
+            const siteHomeId = CoreSites.getCurrentSiteHomeId();
 
             if ('contacts' in courses[0]) {
                 courses = (courses as CoreCourseSearchedData[]).filter((course) => course.id != siteHomeId);
@@ -316,7 +316,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
         const courseId = isOffline ? offlineEvent.courseid : onlineEvent.course?.id;
 
         this.form.controls.name.setValue(event.name);
-        this.form.controls.timestart.setValue(CoreTimeUtils.instance.toDatetimeFormat(event.timestart * 1000));
+        this.form.controls.timestart.setValue(CoreTimeUtils.toDatetimeFormat(event.timestart * 1000));
         this.form.controls.eventtype.setValue(event.eventtype);
         this.form.controls.categoryid.setValue(event.categoryid || '');
         this.form.controls.courseid.setValue(courseId || '');
@@ -329,7 +329,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
             // It's an offline event, use the data as it is.
             this.form.controls.duration.setValue(offlineEvent.duration);
             this.form.controls.timedurationuntil.setValue(
-                CoreTimeUtils.instance.toDatetimeFormat(((offlineEvent.timedurationuntil || 0) * 1000) || Date.now()),
+                CoreTimeUtils.toDatetimeFormat(((offlineEvent.timedurationuntil || 0) * 1000) || Date.now()),
             );
             this.form.controls.timedurationminutes.setValue(offlineEvent.timedurationminutes || '');
             this.form.controls.repeat.setValue(!!offlineEvent.repeat);
@@ -340,13 +340,13 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
             if (onlineEvent.timeduration > 0) {
                 this.form.controls.duration.setValue(1);
-                this.form.controls.timedurationuntil.setValue(CoreTimeUtils.instance.toDatetimeFormat(
+                this.form.controls.timedurationuntil.setValue(CoreTimeUtils.toDatetimeFormat(
                     (onlineEvent.timestart + onlineEvent.timeduration) * 1000,
                 ));
             } else {
                 // No duration.
                 this.form.controls.duration.setValue(0);
-                this.form.controls.timedurationuntil.setValue(CoreTimeUtils.instance.toDatetimeFormat());
+                this.form.controls.timedurationuntil.setValue(CoreTimeUtils.toDatetimeFormat());
             }
 
             this.form.controls.timedurationminutes.setValue('');
@@ -367,19 +367,19 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
      */
     refreshData(refresher?: CustomEvent<IonRefresher>): void {
         const promises = [
-            AddonCalendar.instance.invalidateAccessInformation(this.courseId),
-            AddonCalendar.instance.invalidateAllowedEventTypes(this.courseId),
+            AddonCalendar.invalidateAccessInformation(this.courseId),
+            AddonCalendar.invalidateAllowedEventTypes(this.courseId),
         ];
 
         if (this.types) {
             if (this.types.category) {
-                promises.push(CoreCourses.instance.invalidateCategories(0, true));
+                promises.push(CoreCourses.invalidateCategories(0, true));
             }
             if (this.types.course || this.types.groups) {
                 if (this.showAll) {
-                    promises.push(CoreCourses.instance.invalidateCoursesByField());
+                    promises.push(CoreCourses.invalidateCoursesByField());
                 } else {
-                    promises.push(CoreCourses.instance.invalidateUserCourses());
+                    promises.push(CoreCourses.invalidateUserCourses());
                 }
             }
         }
@@ -401,14 +401,14 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
             return;
         }
 
-        const modal = await CoreDomUtils.instance.showModalLoading();
+        const modal = await CoreDomUtils.showModalLoading();
 
         try {
             await this.loadGroups(courseId);
 
             this.groupControl.setValue('');
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'Error getting data.');
+            CoreDomUtils.showErrorModalDefault(error, 'Error getting data.');
         }
 
         modal.dismiss();
@@ -424,7 +424,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
         this.loadingGroups = true;
 
         try {
-            this.groups = await CoreGroups.instance.getUserGroupsInCourse(courseId);
+            this.groups = await CoreGroups.getUserGroupsInCourse(courseId);
             this.courseGroupSet = true;
         } finally {
             this.loadingGroups = false;
@@ -448,8 +448,8 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
     async submit(): Promise<void> {
         // Validate data.
         const formData = this.form.value;
-        const timeStartDate = CoreTimeUtils.instance.convertToTimestamp(formData.timestart);
-        const timeUntilDate = CoreTimeUtils.instance.convertToTimestamp(formData.timedurationuntil);
+        const timeStartDate = CoreTimeUtils.convertToTimestamp(formData.timestart);
+        const timeUntilDate = CoreTimeUtils.convertToTimestamp(formData.timedurationuntil);
         const timeDurationMinutes = parseInt(formData.timedurationminutes || '', 10);
         let error: string | undefined;
 
@@ -469,7 +469,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
         if (error) {
             // Show error and stop.
-            CoreDomUtils.instance.showErrorModal(Translate.instance.instant(error));
+            CoreDomUtils.showErrorModal(Translate.instant(error));
 
             return;
         }
@@ -513,14 +513,14 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
         }
 
         // Send the data.
-        const modal = await CoreDomUtils.instance.showModalLoading('core.sending', true);
+        const modal = await CoreDomUtils.showModalLoading('core.sending', true);
         let event: AddonCalendarEvent | AddonCalendarOfflineEventDBRecord;
 
         try {
-            const result = await AddonCalendar.instance.submitEvent(this.eventId, data);
+            const result = await AddonCalendar.submitEvent(this.eventId, data);
             event = result.event;
 
-            CoreDomUtils.instance.triggerFormSubmittedEvent(this.formElement, result.sent, this.currentSite.getId());
+            CoreDomUtils.triggerFormSubmittedEvent(this.formElement, result.sent, this.currentSite.getId());
 
             if (result.sent) {
                 // Event created or edited, invalidate right days & months.
@@ -528,7 +528,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
                     (data.repeateditall && this.otherEventsCount ? this.otherEventsCount + 1 : 1);
 
                 try {
-                    await AddonCalendarHelper.instance.refreshAfterChangeEvent(result.event, numberOfRepetitions);
+                    await AddonCalendarHelper.refreshAfterChangeEvent(result.event, numberOfRepetitions);
                 } catch  {
                     // Ignore errors.
                 }
@@ -536,7 +536,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
 
             this.returnToList(event);
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'Error sending data.');
+            CoreDomUtils.showErrorModalDefault(error, 'Error sending data.');
         }
 
         modal.dismiss();
@@ -574,10 +574,10 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
             // Empty form.
             this.hasOffline = false;
             this.form.reset(this.originalData);
-            this.originalData = CoreUtils.instance.clone(this.form.value);
+            this.originalData = CoreUtils.clone(this.form.value);
         } else {
             this.originalData = undefined; // Avoid asking for confirmation.
-            CoreNavigator.instance.back();
+            CoreNavigator.back();
         }
     }
 
@@ -586,16 +586,16 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
      */
     async discard(): Promise<void> {
         try {
-            await CoreDomUtils.instance.showConfirm(Translate.instance.instant('core.areyousure'));
+            await CoreDomUtils.showConfirm(Translate.instant('core.areyousure'));
             try {
-                await AddonCalendarOffline.instance.deleteEvent(this.eventId!);
+                await AddonCalendarOffline.deleteEvent(this.eventId!);
 
-                CoreDomUtils.instance.triggerFormCancelledEvent(this.formElement, this.currentSite.getId());
+                CoreDomUtils.triggerFormCancelledEvent(this.formElement, this.currentSite.getId());
 
                 this.returnToList();
             } catch {
                 // Shouldn't happen.
-                CoreDomUtils.instance.showErrorModal('Error discarding event.');
+                CoreDomUtils.showErrorModal('Error discarding event.');
             }
         } catch {
             // Ignore errors
@@ -608,12 +608,12 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
      * @return Resolved if we can leave it, rejected if not.
      */
     async ionViewCanLeave(): Promise<void> {
-        if (AddonCalendarHelper.instance.hasEventDataChanged(this.form.value, this.originalData)) {
+        if (AddonCalendarHelper.hasEventDataChanged(this.form.value, this.originalData)) {
             // Show confirmation if some data has been modified.
-            await CoreDomUtils.instance.showConfirm(Translate.instance.instant('core.confirmcanceledit'));
+            await CoreDomUtils.showConfirm(Translate.instant('core.confirmcanceledit'));
         }
 
-        CoreDomUtils.instance.triggerFormCancelledEvent(this.formElement, this.currentSite.getId());
+        CoreDomUtils.triggerFormCancelledEvent(this.formElement, this.currentSite.getId());
     }
 
     /**
@@ -621,7 +621,7 @@ export class AddonCalendarEditEventPage implements OnInit, OnDestroy {
      */
     protected unblockSync(): void {
         if (this.eventId) {
-            CoreSync.instance.unblockOperation(AddonCalendarProvider.COMPONENT, this.eventId);
+            CoreSync.unblockOperation(AddonCalendarProvider.COMPONENT, this.eventId);
         }
     }
 

src/addons/calendar/pages/event/event.page.ts

@@ -93,14 +93,14 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
         protected route: ActivatedRoute,
     ) {
 
-        this.notificationsEnabled = CoreLocalNotifications.instance.isAvailable();
-        this.siteHomeId = CoreSites.instance.getCurrentSiteHomeId();
-        this.currentSiteId = CoreSites.instance.getCurrentSiteId();
+        this.notificationsEnabled = CoreLocalNotifications.isAvailable();
+        this.siteHomeId = CoreSites.getCurrentSiteHomeId();
+        this.currentSiteId = CoreSites.getCurrentSiteId();
         this.isSplitViewOn = this.svComponent?.outletActivated;
 
         // Check if site supports editing and deleting. No need to check allowed types, event.canedit already does it.
-        this.canEdit = AddonCalendar.instance.canEditEventsInSite();
-        this.canDelete = AddonCalendar.instance.canDeleteEventsInSite();
+        this.canEdit = AddonCalendar.canEditEventsInSite();
+        this.canDelete = AddonCalendar.canDeleteEventsInSite();
 
         this.asyncConstructor();
 
@@ -127,23 +127,23 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
         );
 
         // Refresh online status when changes.
-        this.onlineObserver = Network.instance.onChange().subscribe(() => {
+        this.onlineObserver = Network.onChange().subscribe(() => {
             // Execute the callback in the Angular zone, so change detection doesn't stop working.
-            NgZone.instance.run(() => {
-                this.isOnline = CoreApp.instance.isOnline();
+            NgZone.run(() => {
+                this.isOnline = CoreApp.isOnline();
             });
         });
     }
 
     protected async asyncConstructor(): Promise<void> {
         if (this.notificationsEnabled) {
-            this.reminders = await AddonCalendar.instance.getEventReminders(this.eventId);
-            this.defaultTime = await AddonCalendar.instance.getDefaultNotificationTime() * 60;
+            this.reminders = await AddonCalendar.getEventReminders(this.eventId);
+            this.defaultTime = await AddonCalendar.getDefaultNotificationTime() * 60;
 
             // Calculate format to use.
             this.notificationFormat =
-                CoreTimeUtils.instance.fixFormatForDatetime(CoreTimeUtils.instance.convertPHPToMoment(
-                    Translate.instance.instant('core.strftimedatetime'),
+                CoreTimeUtils.fixFormatForDatetime(CoreTimeUtils.convertPHPToMoment(
+                    Translate.instant('core.strftimedatetime'),
                 ));
         }
     }
@@ -155,10 +155,10 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
         this.route.queryParams.subscribe(() => {
             this.eventLoaded = false;
 
-            const eventId = CoreNavigator.instance.getRouteNumberParam('id');
+            const eventId = CoreNavigator.getRouteNumberParam('id');
             if (!eventId) {
-                CoreDomUtils.instance.showErrorModal('Event ID not supplied.');
-                CoreNavigator.instance.back();
+                CoreDomUtils.showErrorModal('Event ID not supplied.');
+                CoreNavigator.back();
 
                 return;
             }
@@ -178,18 +178,18 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
      * @return Promise resolved when done.
      */
     async fetchEvent(sync = false, showErrors = false): Promise<void> {
-        const currentSite = CoreSites.instance.getCurrentSite();
-        const canGetById = AddonCalendar.instance.isGetEventByIdAvailableInSite();
+        const currentSite = CoreSites.getCurrentSite();
+        const canGetById = AddonCalendar.isGetEventByIdAvailableInSite();
         let deleted = false;
 
-        this.isOnline = CoreApp.instance.isOnline();
+        this.isOnline = CoreApp.isOnline();
 
         if (sync) {
             // Try to synchronize offline events.
             try {
-                const result = await AddonCalendarSync.instance.syncEvents();
+                const result = await AddonCalendarSync.syncEvents();
                 if (result.warnings && result.warnings.length) {
-                    CoreDomUtils.instance.showErrorModal(result.warnings[0]);
+                    CoreDomUtils.showErrorModal(result.warnings[0]);
                 }
 
                 if (result.deleted && result.deleted.indexOf(this.eventId) != -1) {
@@ -209,7 +209,7 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
                 }
             } catch (error) {
                 if (showErrors) {
-                    CoreDomUtils.instance.showErrorModalDefault(error, 'core.errorsync', true);
+                    CoreDomUtils.showErrorModalDefault(error, 'core.errorsync', true);
                 }
             }
         }
@@ -222,15 +222,15 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
             let event: AddonCalendarEvent | AddonCalendarEventBase | AddonCalendarGetEventsEvent;
             // Get the event data.
             if (canGetById) {
-                event = await AddonCalendar.instance.getEventById(this.eventId);
+                event = await AddonCalendar.getEventById(this.eventId);
             } else {
-                event = await AddonCalendar.instance.getEvent(this.eventId);
+                event = await AddonCalendar.getEvent(this.eventId);
             }
-            this.event = AddonCalendarHelper.instance.formatEventData(event);
+            this.event = AddonCalendarHelper.formatEventData(event);
 
             try {
-                const offlineEvent = AddonCalendarHelper.instance.formatOfflineEventData(
-                    await AddonCalendarOffline.instance.getEvent(this.eventId),
+                const offlineEvent = AddonCalendarHelper.formatOfflineEventData(
+                    await AddonCalendarOffline.getEvent(this.eventId),
                 );
 
                 // There is offline data, apply it.
@@ -242,9 +242,9 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
                 this.hasOffline = false;
             }
 
-            this.currentTime = CoreTimeUtils.instance.timestamp();
-            this.notificationMin = CoreTimeUtils.instance.userDate(this.currentTime * 1000, 'YYYY-MM-DDTHH:mm', false);
-            this.notificationMax = CoreTimeUtils.instance.userDate(
+            this.currentTime = CoreTimeUtils.timestamp();
+            this.notificationMin = CoreTimeUtils.userDate(this.currentTime * 1000, 'YYYY-MM-DDTHH:mm', false);
+            this.notificationMax = CoreTimeUtils.userDate(
                 (this.event!.timestart + this.event!.timeduration) * 1000,
                 'YYYY-MM-DDTHH:mm',
                 false,
@@ -258,7 +258,7 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
 
             if (this.event!.moduleIcon) {
                 // It's a module event, translate the module name to the current language.
-                const name = CoreCourse.instance.translateModuleName(this.event!.modulename || '');
+                const name = CoreCourse.translateModuleName(this.event!.modulename || '');
                 if (name.indexOf('core.mod_') === -1) {
                     this.event!.modulename = name;
                 }
@@ -280,10 +280,10 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
                     this.courseUrl = this.event.course.viewurl;
                 } else if (!canGetById && this.event.courseid ) {
                     // Retrieve the course.
-                    promises.push(CoreCourses.instance.getUserCourse(this.event.courseid, true).then((course) => {
+                    promises.push(CoreCourses.getUserCourse(this.event.courseid, true).then((course) => {
                         this.courseId = course.id;
                         this.courseName = course.fullname;
-                        this.courseUrl = currentSite ? CoreTextUtils.instance.concatenatePaths(
+                        this.courseUrl = currentSite ? CoreTextUtils.concatenatePaths(
                             currentSite.siteUrl,
                             '/course/view.php?id=' + this.courseId,
                         ) : '';
@@ -297,7 +297,7 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
 
             // If it's a group event, get the name of the group.
             if (courseId && this.event.groupid) {
-                promises.push(CoreGroups.instance.getUserGroupsInCourse(courseId).then((groups) => {
+                promises.push(CoreGroups.getUserGroupsInCourse(courseId).then((groups) => {
                     const group = groups.find((group) => group.id == this.event!.groupid);
 
                     this.groupName = group ? group.name : '';
@@ -315,27 +315,27 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
 
             if (this.event.location) {
                 // Build a link to open the address in maps.
-                this.event.location = CoreTextUtils.instance.decodeHTML(this.event.location);
-                this.event.encodedLocation = CoreTextUtils.instance.buildAddressURL(this.event.location);
+                this.event.location = CoreTextUtils.decodeHTML(this.event.location);
+                this.event.encodedLocation = CoreTextUtils.buildAddressURL(this.event.location);
             }
 
             // Check if event was deleted in offine.
-            promises.push(AddonCalendarOffline.instance.isEventDeleted(this.eventId).then((deleted) => {
+            promises.push(AddonCalendarOffline.isEventDeleted(this.eventId).then((deleted) => {
                 this.event!.deleted = deleted;
 
                 return;
             }));
 
             // Re-calculate the formatted time so it uses the device date.
-            promises.push(AddonCalendar.instance.getCalendarTimeFormat().then(async (timeFormat) => {
-                this.event!.formattedtime = await AddonCalendar.instance.formatEventTime(this.event!, timeFormat);
+            promises.push(AddonCalendar.getCalendarTimeFormat().then(async (timeFormat) => {
+                this.event!.formattedtime = await AddonCalendar.formatEventTime(this.event!, timeFormat);
 
                 return;
             }));
 
             await Promise.all(promises);
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevent', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevent', true);
         }
 
         this.eventLoaded = true;
@@ -347,9 +347,9 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
      */
     async addNotificationTime(): Promise<void> {
         if (this.notificationTimeText && this.event && this.event.id) {
-            let notificationTime = CoreTimeUtils.instance.convertToTimestamp(this.notificationTimeText);
+            let notificationTime = CoreTimeUtils.convertToTimestamp(this.notificationTimeText);
 
-            const currentTime = CoreTimeUtils.instance.timestamp();
+            const currentTime = CoreTimeUtils.timestamp();
             const minute = Math.floor(currentTime / 60) * 60;
 
             // Check if the notification time is in the same minute as we are, so the notification is triggered.
@@ -357,8 +357,8 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
                 notificationTime  = currentTime + 1;
             }
 
-            await AddonCalendar.instance.addEventReminder(this.event, notificationTime);
-            this.reminders = await AddonCalendar.instance.getEventReminders(this.eventId);
+            await AddonCalendar.addEventReminder(this.event, notificationTime);
+            this.reminders = await AddonCalendar.getEventReminders(this.eventId);
             this.notificationTimeText = undefined;
         }
     }
@@ -374,15 +374,15 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
         e.stopPropagation();
 
         try {
-            await CoreDomUtils.instance.showDeleteConfirm();
+            await CoreDomUtils.showDeleteConfirm();
 
-            const modal = await CoreDomUtils.instance.showModalLoading('core.deleting', true);
+            const modal = await CoreDomUtils.showModalLoading('core.deleting', true);
 
             try {
-                await AddonCalendar.instance.deleteEventReminder(id);
-                this.reminders = await AddonCalendar.instance.getEventReminders(this.eventId);
+                await AddonCalendar.deleteEventReminder(id);
+                this.reminders = await AddonCalendar.getEventReminders(this.eventId);
             } catch (error) {
-                CoreDomUtils.instance.showErrorModalDefault(error, 'Error deleting reminder');
+                CoreDomUtils.showErrorModalDefault(error, 'Error deleting reminder');
             } finally {
                 modal.dismiss();
             }
@@ -422,10 +422,10 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
 
         const promises: Promise<void>[] = [];
 
-        promises.push(AddonCalendar.instance.invalidateEvent(this.eventId));
-        promises.push(AddonCalendar.instance.invalidateTimeFormat());
+        promises.push(AddonCalendar.invalidateEvent(this.eventId));
+        promises.push(AddonCalendar.invalidateTimeFormat());
 
-        await CoreUtils.instance.allPromisesIgnoringErrors(promises);
+        await CoreUtils.allPromisesIgnoringErrors(promises);
 
         await this.fetchEvent(sync, showErrors);
     }
@@ -436,7 +436,7 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
     openEdit(): void {
         // Decide which navCtrl to use. If this page is inside a split view, use the split view's master nav.
         // @todo const navCtrl = this.svComponent ? this.svComponent.getMasterNav() : this.navCtrl;
-        CoreNavigator.instance.navigateToSitePath('/calendar/edit', { params: { eventId: this.eventId } });
+        CoreNavigator.navigateToSitePath('/calendar/edit', { params: { eventId: this.eventId } });
     }
 
     /**
@@ -447,13 +447,13 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
             return;
         }
 
-        const title = Translate.instance.instant('addon.calendar.deleteevent');
+        const title = Translate.instant('addon.calendar.deleteevent');
         const options: AlertOptions = {};
         let message: string;
 
         if (this.event.eventcount > 1) {
             // It's a repeated event.
-            message = Translate.instance.instant(
+            message = Translate.instant(
                 'addon.calendar.confirmeventseriesdelete',
                 { $a: { name: this.event.name, count: this.event.eventcount } },
             );
@@ -464,39 +464,39 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
                     name: 'deleteall',
                     checked: true,
                     value: false,
-                    label: Translate.instance.instant('addon.calendar.deleteoneevent'),
+                    label: Translate.instant('addon.calendar.deleteoneevent'),
                 },
                 {
                     type: 'radio',
                     name: 'deleteall',
                     checked: false,
                     value: true,
-                    label: Translate.instance.instant('addon.calendar.deleteallevents'),
+                    label: Translate.instant('addon.calendar.deleteallevents'),
                 },
             ];
         } else {
             // Not repeated, display a simple confirm.
-            message = Translate.instance.instant('addon.calendar.confirmeventdelete', { $a: this.event.name });
+            message = Translate.instant('addon.calendar.confirmeventdelete', { $a: this.event.name });
         }
 
         let deleteAll = false;
         try {
-            deleteAll = await CoreDomUtils.instance.showConfirm(message, title, undefined, undefined, options);
+            deleteAll = await CoreDomUtils.showConfirm(message, title, undefined, undefined, options);
         } catch {
 
             // User canceled.
             return;
         }
 
-        const modal = await CoreDomUtils.instance.showModalLoading('core.sending', true);
+        const modal = await CoreDomUtils.showModalLoading('core.sending', true);
 
         try {
-            const sent = await AddonCalendar.instance.deleteEvent(this.event.id, this.event.name, deleteAll);
+            const sent = await AddonCalendar.deleteEvent(this.event.id, this.event.name, deleteAll);
 
             if (sent) {
                 // Event deleted, invalidate right days & months.
                 try {
-                    await AddonCalendarHelper.instance.refreshAfterChangeEvent(this.event, deleteAll ? this.event.eventcount : 1);
+                    await AddonCalendarHelper.refreshAfterChangeEvent(this.event, deleteAll ? this.event.eventcount : 1);
                 } catch {
                     // Ignore errors.
                 }
@@ -506,21 +506,21 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
             CoreEvents.trigger<AddonCalendarUpdatedEventEvent>(AddonCalendarProvider.DELETED_EVENT_EVENT, {
                 eventId: this.eventId,
                 sent: sent,
-            }, CoreSites.instance.getCurrentSiteId());
+            }, CoreSites.getCurrentSiteId());
 
             if (sent) {
-                CoreDomUtils.instance.showToast('addon.calendar.eventcalendareventdeleted', true, 3000);
+                CoreDomUtils.showToast('addon.calendar.eventcalendareventdeleted', true, 3000);
 
                 // Event deleted, close the view.
-                if (CoreScreen.instance.isMobile) {
-                    CoreNavigator.instance.back();
+                if (CoreScreen.isMobile) {
+                    CoreNavigator.back();
                 }
             } else {
                 // Event deleted in offline, just mark it as deleted.
                 this.event.deleted = true;
             }
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'Error deleting event.');
+            CoreDomUtils.showErrorModalDefault(error, 'Error deleting event.');
         }
 
         modal.dismiss();
@@ -534,21 +534,21 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
             return;
         }
 
-        const modal = await CoreDomUtils.instance.showModalLoading('core.sending', true);
+        const modal = await CoreDomUtils.showModalLoading('core.sending', true);
 
         try {
 
-            await AddonCalendarOffline.instance.unmarkDeleted(this.event.id);
+            await AddonCalendarOffline.unmarkDeleted(this.event.id);
 
             // Trigger an event.
             CoreEvents.trigger<AddonCalendarUpdatedEventEvent>(AddonCalendarProvider.UNDELETED_EVENT_EVENT, {
                 eventId: this.eventId,
-            }, CoreSites.instance.getCurrentSiteId());
+            }, CoreSites.getCurrentSiteId());
 
             this.event.deleted = false;
 
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'Error undeleting event.');
+            CoreDomUtils.showErrorModalDefault(error, 'Error undeleting event.');
         }
 
         modal.dismiss();
@@ -566,11 +566,11 @@ export class AddonCalendarEventPage implements OnInit, OnDestroy {
         }
 
         if (data.deleted && data.deleted.indexOf(this.eventId) != -1) {
-            CoreDomUtils.instance.showToast('addon.calendar.eventcalendareventdeleted', true, 3000);
+            CoreDomUtils.showToast('addon.calendar.eventcalendareventdeleted', true, 3000);
 
             // Event was deleted, close the view.
-            if (CoreScreen.instance.isMobile) {
-                CoreNavigator.instance.back();
+            if (CoreScreen.isMobile) {
+                CoreNavigator.back();
             }
         } else if (data.events && (!isManual || data.source != 'event')) {
             const event = data.events.find((ev) => ev.id == this.eventId);

src/addons/calendar/pages/index/index.page.ts

@@ -86,7 +86,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
     constructor(
         protected route: ActivatedRoute,
     ) {
-        this.currentSiteId = CoreSites.instance.getCurrentSiteId();
+        this.currentSiteId = CoreSites.getCurrentSiteId();
 
         // Listen for events added. When an event is added, reload the data.
         this.newEventObserver = CoreEvents.on<AddonCalendarUpdatedEventEvent>(
@@ -140,7 +140,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
 
         // Update the "hasOffline" property if an event deleted in offline is restored.
         this.undeleteEventObserver = CoreEvents.on(AddonCalendarProvider.UNDELETED_EVENT_EVENT, async () => {
-            this.hasOffline = await AddonCalendarOffline.instance.hasOfflineData();
+            this.hasOffline = await AddonCalendarOffline.hasOfflineData();
         }, this.currentSiteId);
 
         this.filterChangedObserver = CoreEvents.on<AddonCalendarFilter>(
@@ -149,15 +149,15 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
                 this.filter = filterData;
 
                 // Course viewed has changed, check if the user can create events for this course calendar.
-                this.canCreate = await AddonCalendarHelper.instance.canEditEvents(this.filter['courseId']);
+                this.canCreate = await AddonCalendarHelper.canEditEvents(this.filter['courseId']);
             },
         );
 
         // Refresh online status when changes.
-        this.onlineObserver = Network.instance.onChange().subscribe(() => {
+        this.onlineObserver = Network.onChange().subscribe(() => {
             // Execute the callback in the Angular zone, so change detection doesn't stop working.
-            NgZone.instance.run(() => {
-                this.isOnline = CoreApp.instance.isOnline();
+            NgZone.run(() => {
+                this.isOnline = CoreApp.isOnline();
             });
         });
     }
@@ -166,14 +166,14 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
      * View loaded.
      */
     ngOnInit(): void {
-        this.notificationsEnabled = CoreLocalNotifications.instance.isAvailable();
+        this.notificationsEnabled = CoreLocalNotifications.isAvailable();
 
         this.route.queryParams.subscribe(() => {
-            this.eventId = CoreNavigator.instance.getRouteNumberParam('eventId');
-            this.filter.courseId = CoreNavigator.instance.getRouteNumberParam('courseId') || -1;
-            this.year = CoreNavigator.instance.getRouteNumberParam('year');
-            this.month = CoreNavigator.instance.getRouteNumberParam('month');
-            this.loadUpcoming = !!CoreNavigator.instance.getRouteBooleanParam('upcoming');
+            this.eventId = CoreNavigator.getRouteNumberParam('eventId');
+            this.filter.courseId = CoreNavigator.getRouteNumberParam('courseId') || -1;
+            this.year = CoreNavigator.getRouteNumberParam('year');
+            this.month = CoreNavigator.getRouteNumberParam('month');
+            this.loadUpcoming = !!CoreNavigator.getRouteBooleanParam('upcoming');
             this.showCalendar = !this.loadUpcoming;
             this.filter.filtered = this.filter.courseId > 0;
 
@@ -196,14 +196,14 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
     async fetchData(sync?: boolean, showErrors?: boolean): Promise<void> {
 
         this.syncIcon = CoreConstants.ICON_LOADING;
-        this.isOnline = CoreApp.instance.isOnline();
+        this.isOnline = CoreApp.isOnline();
 
         if (sync) {
             // Try to synchronize offline events.
             try {
-                const result = await AddonCalendarSync.instance.syncEvents();
+                const result = await AddonCalendarSync.syncEvents();
                 if (result.warnings && result.warnings.length) {
-                    CoreDomUtils.instance.showErrorModal(result.warnings[0]);
+                    CoreDomUtils.showErrorModal(result.warnings[0]);
                 }
 
                 if (result.updated) {
@@ -218,7 +218,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
                 }
             } catch (error) {
                 if (showErrors) {
-                    CoreDomUtils.instance.showErrorModalDefault(error, 'core.errorsync', true);
+                    CoreDomUtils.showErrorModalDefault(error, 'core.errorsync', true);
                 }
             }
         }
@@ -229,21 +229,21 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
             this.hasOffline = false;
 
             // Load courses for the popover.
-            promises.push(CoreCoursesHelper.instance.getCoursesForPopover(this.filter.courseId).then((data) => {
+            promises.push(CoreCoursesHelper.getCoursesForPopover(this.filter.courseId).then((data) => {
                 this.courses = data.courses;
 
                 return;
             }));
 
             // Check if user can create events.
-            promises.push(AddonCalendarHelper.instance.canEditEvents(this.filter.courseId).then((canEdit) => {
+            promises.push(AddonCalendarHelper.canEditEvents(this.filter.courseId).then((canEdit) => {
                 this.canCreate = canEdit;
 
                 return;
             }));
 
             // Check if there is offline data.
-            promises.push(AddonCalendarOffline.instance.hasOfflineData().then((hasOffline) => {
+            promises.push(AddonCalendarOffline.hasOfflineData().then((hasOffline) => {
                 this.hasOffline = hasOffline;
 
                 return;
@@ -251,7 +251,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
 
             await Promise.all(promises);
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
         }
 
         this.loaded = true;
@@ -290,7 +290,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
 
         const promises: Promise<void>[] = [];
 
-        promises.push(AddonCalendar.instance.invalidateAllowedEventTypes());
+        promises.push(AddonCalendar.invalidateAllowedEventTypes());
 
         // Refresh the sub-component.
         if (this.showCalendar && this.calendarComponent) {
@@ -312,7 +312,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
             // It's an offline event, go to the edit page.
             this.openEdit(eventId);
         } else {
-            CoreNavigator.instance.navigateToSitePath('/calendar/event', { params: { id: eventId } });
+            CoreNavigator.navigateToSitePath('/calendar/event', { params: { id: eventId } });
         }
     }
 
@@ -332,7 +332,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
             params[key] = this.filter[key];
         });
 
-        CoreNavigator.instance.navigateToSitePath('/calendar/day', { params });
+        CoreNavigator.navigateToSitePath('/calendar/day', { params });
     }
 
     /**
@@ -341,7 +341,7 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
      * @param event Event.
      */
     async openFilter(event: MouseEvent): Promise<void> {
-        const popover = await PopoverController.instance.create({
+        const popover = await PopoverController.create({
             component: AddonCalendarFilterPopoverComponent,
             componentProps: {
                 courses: this.courses,
@@ -367,14 +367,14 @@ export class AddonCalendarIndexPage implements OnInit, OnDestroy {
             params.courseId = this.filter.courseId;
         }
 
-        CoreNavigator.instance.navigateToSitePath('/calendar/edit', { params });
+        CoreNavigator.navigateToSitePath('/calendar/edit', { params });
     }
 
     /**
      * Open calendar events settings.
      */
     openSettings(): void {
-        CoreNavigator.instance.navigateToSitePath('/calendar/settings');
+        CoreNavigator.navigateToSitePath('/calendar/settings');
     }
 
     /**

src/addons/calendar/pages/list/list.module.ts

@@ -43,8 +43,8 @@ const tabletRoutes: Routes = [
 ];
 
 const routes: Routes = [
-    ...conditionalRoutes(mobileRoutes, () => CoreScreen.instance.isMobile),
-    ...conditionalRoutes(tabletRoutes, () => CoreScreen.instance.isTablet),
+    ...conditionalRoutes(mobileRoutes, () => CoreScreen.isMobile),
+    ...conditionalRoutes(tabletRoutes, () => CoreScreen.isTablet),
 ];
 
 

src/addons/calendar/pages/list/list.page.ts

@@ -103,14 +103,14 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
 
     constructor() {
 
-        this.siteHomeId = CoreSites.instance.getCurrentSiteHomeId();
-        this.notificationsEnabled = CoreLocalNotifications.instance.isAvailable();
-        this.currentSiteId = CoreSites.instance.getCurrentSiteId();
+        this.siteHomeId = CoreSites.getCurrentSiteHomeId();
+        this.notificationsEnabled = CoreLocalNotifications.isAvailable();
+        this.currentSiteId = CoreSites.getCurrentSiteId();
 
         if (this.notificationsEnabled) {
             // Re-schedule events if default time changes.
             this.obsDefaultTimeChange = CoreEvents.on(AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_CHANGED, () => {
-                AddonCalendar.instance.scheduleEventsNotifications(this.onlineEvents);
+                AddonCalendar.scheduleEventsNotifications(this.onlineEvents);
             }, this.currentSiteId);
         }
 
@@ -225,7 +225,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
                 this.filter = data;
 
                 // Course viewed has changed, check if the user can create events for this course calendar.
-                this.canCreate = await AddonCalendarHelper.instance.canEditEvents(this.filter.courseId);
+                this.canCreate = await AddonCalendarHelper.canEditEvents(this.filter.courseId);
 
                 this.filterEvents();
 
@@ -233,10 +233,10 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
             });
 
         // Refresh online status when changes.
-        this.onlineObserver = Network.instance.onChange().subscribe(() => {
+        this.onlineObserver = Network.onChange().subscribe(() => {
             // Execute the callback in the Angular zone, so change detection doesn't stop working.
-            NgZone.instance.run(() => {
-                this.isOnline = CoreApp.instance.isOnline();
+            NgZone.run(() => {
+                this.isOnline = CoreApp.isOnline();
             });
         });
     }
@@ -245,8 +245,8 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
      * View loaded.
      */
     async ngOnInit(): Promise<void> {
-        this.eventId = CoreNavigator.instance.getRouteNumberParam('eventId');
-        this.filter.courseId = CoreNavigator.instance.getRouteNumberParam('courseId') || -1;
+        this.eventId = CoreNavigator.getRouteNumberParam('eventId');
+        this.filter.courseId = CoreNavigator.getRouteNumberParam('courseId') || -1;
 
         if (this.eventId) {
             // There is an event to load, open the event in a new state.
@@ -272,10 +272,10 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
      */
     protected emptySplitView(): void {
         // Empty details.
-        const splitViewLoaded = CoreNavigator.instance.isCurrentPathInTablet('**/calendar/list/event') ||
-            CoreNavigator.instance.isCurrentPathInTablet('**/calendar/list/edit');
+        const splitViewLoaded = CoreNavigator.isCurrentPathInTablet('**/calendar/list/event') ||
+            CoreNavigator.isCurrentPathInTablet('**/calendar/list/edit');
         if (splitViewLoaded) {
-            CoreNavigator.instance.navigate('../');
+            CoreNavigator.navigate('../');
         }
     }
 
@@ -288,17 +288,17 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
      * @return Promise resolved when done.
      */
     async fetchData(refresh = false, sync = false, showErrors = false): Promise<void> {
-        this.initialTime = CoreTimeUtils.instance.timestamp();
+        this.initialTime = CoreTimeUtils.timestamp();
         this.daysLoaded = 0;
         this.emptyEventsTimes = 0;
-        this.isOnline = CoreApp.instance.isOnline();
+        this.isOnline = CoreApp.isOnline();
 
         if (sync) {
             // Try to synchronize offline events.
             try {
-                const result = await AddonCalendarSync.instance.syncEvents();
+                const result = await AddonCalendarSync.syncEvents();
                 if (result.warnings && result.warnings.length) {
-                    CoreDomUtils.instance.showErrorModal(result.warnings[0]);
+                    CoreDomUtils.showErrorModal(result.warnings[0]);
                 }
 
                 if (result.updated) {
@@ -313,7 +313,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
                 }
             } catch (error) {
                 if (showErrors) {
-                    CoreDomUtils.instance.showErrorModalDefault(error, 'core.errorsync', true);
+                    CoreDomUtils.showErrorModalDefault(error, 'core.errorsync', true);
                 }
             }
         }
@@ -323,34 +323,34 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
 
             this.hasOffline = false;
 
-            promises.push(AddonCalendarHelper.instance.canEditEvents(this.filter.courseId).then((canEdit) => {
+            promises.push(AddonCalendarHelper.canEditEvents(this.filter.courseId).then((canEdit) => {
                 this.canCreate = canEdit;
 
                 return;
             }));
 
             // Load courses for the popover.
-            promises.push(CoreCoursesHelper.instance.getCoursesForPopover(this.filter.courseId).then((result) => {
+            promises.push(CoreCoursesHelper.getCoursesForPopover(this.filter.courseId).then((result) => {
                 this.courses = result.courses;
 
                 return this.fetchEvents(refresh);
             }));
 
             // Get offline events.
-            promises.push(AddonCalendarOffline.instance.getAllEditedEvents().then((offlineEvents) => {
+            promises.push(AddonCalendarOffline.getAllEditedEvents().then((offlineEvents) => {
                 this.hasOffline = this.hasOffline || !!offlineEvents.length;
 
                 // Format data and sort by timestart.
                 const events: AddonCalendarEventToDisplay[] = offlineEvents.map((event) =>
-                    AddonCalendarHelper.instance.formatOfflineEventData(event));
+                    AddonCalendarHelper.formatOfflineEventData(event));
 
-                this.offlineEvents = AddonCalendarHelper.instance.sortEvents(events);
+                this.offlineEvents = AddonCalendarHelper.sortEvents(events);
 
                 return;
             }));
 
             // Get events deleted in offline.
-            promises.push(AddonCalendarOffline.instance.getAllDeletedEventsIds().then((ids) => {
+            promises.push(AddonCalendarOffline.getAllDeletedEventsIds().then((ids) => {
                 this.hasOffline = this.hasOffline || !!ids.length;
                 this.deletedEvents = ids;
 
@@ -359,7 +359,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
 
             await Promise.all(promises);
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
         }
 
         this.eventsLoaded = true;
@@ -377,7 +377,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
 
         try {
             const onlineEventsTemp =
-                await AddonCalendar.instance.getEventsList(this.initialTime, this.daysLoaded, AddonCalendarProvider.DAYS_INTERVAL);
+                await AddonCalendar.getEventsList(this.initialTime, this.daysLoaded, AddonCalendarProvider.DAYS_INTERVAL);
 
             if (onlineEventsTemp.length === 0) {
                 this.emptyEventsTimes++;
@@ -395,7 +395,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
                     return this.fetchEvents();
                 }
             } else {
-                const onlineEvents = onlineEventsTemp.map((event) => AddonCalendarHelper.instance.formatEventData(event));
+                const onlineEvents = onlineEventsTemp.map((event) => AddonCalendarHelper.formatEventData(event));
 
                 // Get the merged events of this period.
                 const events = this.mergeEvents(onlineEvents);
@@ -407,8 +407,8 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
                     this.events = events;
                 } else {
                     // Filter events with same ID. Repeated events are returned once per WS call, show them only once.
-                    this.onlineEvents = CoreUtils.instance.mergeArraysWithoutDuplicates(this.onlineEvents, onlineEvents, 'id');
-                    this.events = CoreUtils.instance.mergeArraysWithoutDuplicates(this.events, events, 'id');
+                    this.onlineEvents = CoreUtils.mergeArraysWithoutDuplicates(this.onlineEvents, onlineEvents, 'id');
+                    this.events = CoreUtils.mergeArraysWithoutDuplicates(this.events, events, 'id');
                 }
                 this.filterEvents();
 
@@ -420,7 +420,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
                 this.canLoadMore = true;
 
                 // Schedule notifications for the events retrieved (might have new events).
-                AddonCalendar.instance.scheduleEventsNotifications(this.onlineEvents);
+                AddonCalendar.scheduleEventsNotifications(this.onlineEvents);
 
                 this.daysLoaded += AddonCalendarProvider.DAYS_INTERVAL;
             }
@@ -429,7 +429,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
             // @todo: Infinite loading is not working if content is not high enough.
             // this.content.resize();
         } catch (error) {
-            CoreDomUtils.instance.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
+            CoreDomUtils.showErrorModalDefault(error, 'addon.calendar.errorloadevents', true);
             this.loadMoreError = true; // Set to prevent infinite calls with infinite-loading.
         }
 
@@ -454,7 +454,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
     }
 
     protected filterEvents(): void {
-        this.filteredEvents = AddonCalendarHelper.instance.getFilteredEvents(this.events, this.filter, this.categories);
+        this.filteredEvents = AddonCalendarHelper.getFilteredEvents(this.events, this.filter, this.categories);
     }
 
     /**
@@ -482,7 +482,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
      */
     protected async loadCategories(): Promise<void> {
         try {
-            const cats = await CoreCourses.instance.getCategories(0, true);
+            const cats = await CoreCourses.getCategories(0, true);
             this.categoriesRetrieved = true;
             this.categories = {};
             // Index categories by ID.
@@ -539,7 +539,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
         // Merge both arrays and sort them.
         result = result.concat(periodOfflineEvents);
 
-        return AddonCalendarHelper.instance.sortEvents(result);
+        return AddonCalendarHelper.sortEvents(result);
     }
 
     /**
@@ -573,11 +573,11 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
 
         const promises: Promise<void>[] = [];
 
-        promises.push(AddonCalendar.instance.invalidateEventsList());
-        promises.push(AddonCalendar.instance.invalidateAllowedEventTypes());
+        promises.push(AddonCalendar.invalidateEventsList());
+        promises.push(AddonCalendar.invalidateAllowedEventTypes());
 
         if (this.categoriesRetrieved) {
-            promises.push(CoreCourses.instance.invalidateCategories(0, true));
+            promises.push(CoreCourses.invalidateCategories(0, true));
             this.categoriesRetrieved = false;
         }
 
@@ -624,7 +624,7 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
      * @param event Event.
      */
     async openFilter(event: MouseEvent): Promise<void> {
-        const popover = await PopoverController.instance.create({
+        const popover = await PopoverController.create({
             component: AddonCalendarFilterPopoverComponent,
             componentProps: {
                 courses: this.courses,
@@ -652,17 +652,17 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
             params.courseId = this.filter.courseId;
         }
 
-        const splitViewLoaded = CoreNavigator.instance.isCurrentPathInTablet('**/calendar/list/event') ||
-            CoreNavigator.instance.isCurrentPathInTablet('**/calendar/list/edit');
+        const splitViewLoaded = CoreNavigator.isCurrentPathInTablet('**/calendar/list/event') ||
+            CoreNavigator.isCurrentPathInTablet('**/calendar/list/edit');
         const path = (splitViewLoaded ? '../' : '') + 'edit';
-        CoreNavigator.instance.navigate(path, { params });
+        CoreNavigator.navigate(path, { params });
     }
 
     /**
      * Open calendar events settings.
      */
     openSettings(): void {
-        CoreNavigator.instance.navigateToSitePath('/calendar/settings');
+        CoreNavigator.navigateToSitePath('/calendar/settings');
     }
 
     /**
@@ -677,10 +677,10 @@ export class AddonCalendarListPage implements OnInit, OnDestroy {
             // It's an offline event, go to the edit page.
             this.openEdit(eventId);
         } else {
-            const splitViewLoaded = CoreNavigator.instance.isCurrentPathInTablet('**/calendar/list/event') ||
-                CoreNavigator.instance.isCurrentPathInTablet('**/calendar/list/edit');
+            const splitViewLoaded = CoreNavigator.isCurrentPathInTablet('**/calendar/list/event') ||
+                CoreNavigator.isCurrentPathInTablet('**/calendar/list/edit');
             const path = (splitViewLoaded ? '../' : '') + 'event';
-            CoreNavigator.instance.navigate(path, { params: {
+            CoreNavigator.navigate(path, { params: {
                 id: eventId,
             } });
         }

src/addons/calendar/pages/settings/settings.ts

@@ -32,7 +32,7 @@ export class AddonCalendarSettingsPage implements OnInit {
      * View loaded.
      */
     async ngOnInit(): Promise<void> {
-        this.defaultTime = await AddonCalendar.instance.getDefaultNotificationTime();
+        this.defaultTime = await AddonCalendar.getDefaultNotificationTime();
     }
 
     /**
@@ -41,12 +41,12 @@ export class AddonCalendarSettingsPage implements OnInit {
      * @param newTime New time.
      */
     updateDefaultTime(newTime: number): void {
-        AddonCalendar.instance.setDefaultNotificationTime(newTime);
+        AddonCalendar.setDefaultNotificationTime(newTime);
 
         CoreEvents.trigger(
             AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_CHANGED,
             { time: newTime },
-            CoreSites.instance.getCurrentSiteId(),
+            CoreSites.getCurrentSiteId(),
         );
     }
 

src/addons/calendar/services/calendar-helper.ts

@@ -64,7 +64,7 @@ export class AddonCalendarHelperProvider {
      */
     getEventIcon(eventType: AddonCalendarEventType): string {
         if (this.eventTypeIcons.length == 0) {
-            CoreUtils.instance.enumKeys(AddonCalendarEventType).forEach((name) => {
+            CoreUtils.enumKeys(AddonCalendarEventType).forEach((name) => {
                 const value = AddonCalendarEventType[name];
                 this.eventTypeIcons[value] = AddonCalendarEventIcons[name];
             });
@@ -104,12 +104,12 @@ export class AddonCalendarHelperProvider {
      */
     async canEditEvents(courseId?: number, siteId?: string): Promise<boolean> {
         try {
-            const canEdit = await AddonCalendar.instance.canEditEvents(siteId);
+            const canEdit = await AddonCalendar.canEditEvents(siteId);
             if (!canEdit) {
                 return false;
             }
 
-            const types = await AddonCalendar.instance.getAllowedEventTypes(courseId, siteId);
+            const types = await AddonCalendar.getAllowedEventTypes(courseId, siteId);
 
             return Object.keys(types).length > 0;
         } catch {
@@ -129,7 +129,7 @@ export class AddonCalendarHelperProvider {
     ): { [monthId: string]: { [day: number]: AddonCalendarEventToDisplay[] } } {
         // Format data.
         const events: AddonCalendarEventToDisplay[] = offlineEvents.map((event) =>
-            AddonCalendarHelper.instance.formatOfflineEventData(event));
+            AddonCalendarHelper.formatOfflineEventData(event));
 
         const result = {};
 
@@ -180,7 +180,7 @@ export class AddonCalendarHelperProvider {
             userid: event.userid,
             timemodified: event.timemodified,
             eventIcon: this.getEventIcon(event.eventtype),
-            formattedType: AddonCalendar.instance.getEventType(event),
+            formattedType: AddonCalendar.getEventType(event),
             modulename: event.modulename,
             format: 1,
             visible: 1,
@@ -188,11 +188,11 @@ export class AddonCalendarHelperProvider {
         };
 
         if (event.modulename) {
-            eventFormatted.eventIcon = CoreCourse.instance.getModuleIconSrc(event.modulename);
+            eventFormatted.eventIcon = CoreCourse.getModuleIconSrc(event.modulename);
             eventFormatted.moduleIcon = eventFormatted.eventIcon;
         }
 
-        eventFormatted.formattedType = AddonCalendar.instance.getEventType(event);
+        eventFormatted.formattedType = AddonCalendar.getEventType(event);
 
         // Calculate context.
         if ('course' in event) {
@@ -345,10 +345,10 @@ export class AddonCalendarHelperProvider {
         month: number,
         siteId?: string,
     ): Promise<{ daynames: Partial<AddonCalendarDayName>[]; weeks: Partial<AddonCalendarWeek>[] }> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         // Get starting week day user preference, fallback to site configuration.
         let startWeekDayStr = site.getStoredConfig('calendar_startwday');
-        startWeekDayStr = await CoreConfig.instance.get(AddonCalendarProvider.STARTING_WEEK_DAY, startWeekDayStr);
+        startWeekDayStr = await CoreConfig.get(AddonCalendarProvider.STARTING_WEEK_DAY, startWeekDayStr);
         const startWeekDay = parseInt(startWeekDayStr, 10);
 
         const today = moment();
@@ -531,7 +531,7 @@ export class AddonCalendarHelperProvider {
         const eventCourse = (event.course && event.course.id) || event.courseid;
 
         // Show the event if it is from site home or if it matches the selected course.
-        return !!eventCourse && (eventCourse == CoreSites.instance.getCurrentSiteHomeId() || eventCourse == courseId);
+        return !!eventCourse && (eventCourse == CoreSites.getCurrentSiteHomeId() || eventCourse == courseId);
     }
 
     /**
@@ -543,13 +543,13 @@ export class AddonCalendarHelperProvider {
      * @return Resolved when done.
      */
     async refreshAfterChangeEvents(events: AddonCalendarSyncInvalidateEvent[], siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const fetchTimestarts: number[] = [];
         const invalidateTimestarts: number[] = [];
         const promises: Promise<unknown>[] = [];
 
         // Always fetch upcoming events.
-        promises.push(AddonCalendar.instance.getUpcomingEvents(undefined, undefined, true, site.id));
+        promises.push(AddonCalendar.getUpcomingEvents(undefined, undefined, true, site.id));
 
         promises.concat(events.map(async (eventData) => {
 
@@ -557,7 +557,7 @@ export class AddonCalendarHelperProvider {
                 // Not repeated.
                 fetchTimestarts.push(eventData.timestart);
 
-                return AddonCalendar.instance.invalidateEvent(eventData.id);
+                return AddonCalendar.invalidateEvent(eventData.id);
             }
 
             if (eventData.repeatid) {
@@ -573,10 +573,10 @@ export class AddonCalendarHelperProvider {
 
                 // Get the repeated events to invalidate them.
                 const repeatedEvents =
-                    await AddonCalendar.instance.getLocalEventsByRepeatIdFromLocalDb(eventData.repeatid, site.id);
+                    await AddonCalendar.getLocalEventsByRepeatIdFromLocalDb(eventData.repeatid, site.id);
 
-                await CoreUtils.instance.allPromises(repeatedEvents.map((event) =>
-                    AddonCalendar.instance.invalidateEvent(event.id!)));
+                await CoreUtils.allPromises(repeatedEvents.map((event) =>
+                    AddonCalendar.invalidateEvent(event.id!)));
 
                 return;
             }
@@ -596,11 +596,11 @@ export class AddonCalendarHelperProvider {
         }));
 
         try {
-            await CoreUtils.instance.allPromisesIgnoringErrors(promises);
+            await CoreUtils.allPromisesIgnoringErrors(promises);
         } finally {
             const treatedMonths = {};
             const treatedDays = {};
-            const finalPromises: Promise<unknown>[] =[AddonCalendar.instance.invalidateAllUpcomingEvents()];
+            const finalPromises: Promise<unknown>[] =[AddonCalendar.invalidateAllUpcomingEvents()];
 
             // Fetch months and days.
             fetchTimestarts.map((fetchTime) => {
@@ -611,7 +611,7 @@ export class AddonCalendarHelperProvider {
                     // Month not refetch or invalidated already, do it now.
                     treatedMonths[monthId] = true;
 
-                    finalPromises.push(AddonCalendar.instance.getMonthlyEvents(
+                    finalPromises.push(AddonCalendar.getMonthlyEvents(
                         day.year(),
                         day.month() + 1,
                         undefined,
@@ -626,7 +626,7 @@ export class AddonCalendarHelperProvider {
                     // Dat not refetch or invalidated already, do it now.
                     treatedDays[dayId] = true;
 
-                    finalPromises.push(AddonCalendar.instance.getDayEvents(
+                    finalPromises.push(AddonCalendar.getDayEvents(
                         day.year(),
                         day.month() + 1,
                         day.date(),
@@ -647,7 +647,7 @@ export class AddonCalendarHelperProvider {
                     // Month not refetch or invalidated already, do it now.
                     treatedMonths[monthId] = true;
 
-                    finalPromises.push(AddonCalendar.instance.invalidateMonthlyEvents(day.year(), day.month() + 1, site.id));
+                    finalPromises.push(AddonCalendar.invalidateMonthlyEvents(day.year(), day.month() + 1, site.id));
                 }
 
                 const dayId = monthId + '#' + day.date();
@@ -655,7 +655,7 @@ export class AddonCalendarHelperProvider {
                     // Dat not refetch or invalidated already, do it now.
                     treatedDays[dayId] = true;
 
-                    finalPromises.push(AddonCalendar.instance.invalidateDayEvents(
+                    finalPromises.push(AddonCalendar.invalidateDayEvents(
                         day.year(),
                         day.month() + 1,
                         day.date(),
@@ -664,7 +664,7 @@ export class AddonCalendarHelperProvider {
                 }
             });
 
-            await CoreUtils.instance.allPromisesIgnoringErrors(finalPromises);
+            await CoreUtils.allPromisesIgnoringErrors(finalPromises);
         }
     }
 
@@ -714,7 +714,7 @@ export class AddonCalendarHelperProvider {
 
 }
 
-export class AddonCalendarHelper extends makeSingleton(AddonCalendarHelperProvider) {}
+export const AddonCalendarHelper = makeSingleton(AddonCalendarHelperProvider);
 
 /**
  * Calculated data for Calendar filtering.

src/addons/calendar/services/calendar-offline.ts

@@ -39,7 +39,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved if deleted, rejected if failure.
      */
     async deleteEvent(eventId: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const conditions: SQLiteDBRecordValues = {
             id: eventId,
@@ -62,7 +62,7 @@ export class AddonCalendarOfflineProvider {
 
         const result = await Promise.all(promises);
 
-        return CoreUtils.instance.mergeArraysWithoutDuplicates(result[0], result[1]);
+        return CoreUtils.mergeArraysWithoutDuplicates(result[0], result[1]);
     }
 
     /**
@@ -72,7 +72,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved with all the events deleted in offline.
      */
     async getAllDeletedEvents(siteId?: string): Promise<AddonCalendarOfflineDeletedEventDBRecord[]> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return await site.getDb().getRecords(DELETED_EVENTS_TABLE);
     }
@@ -96,7 +96,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved with events.
      */
     async getAllEditedEvents(siteId?: string): Promise<AddonCalendarOfflineEventDBRecord[]> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return await site.getDb().getRecords(EVENTS_TABLE);
     }
@@ -121,7 +121,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved with the deleted event.
      */
     async getDeletedEvent(eventId: number, siteId?: string): Promise<AddonCalendarOfflineDeletedEventDBRecord> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const conditions: SQLiteDBRecordValues = {
             id: eventId,
         };
@@ -137,7 +137,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved with the event.
      */
     async getEvent(eventId: number, siteId?: string): Promise<AddonCalendarOfflineEventDBRecord> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const conditions: SQLiteDBRecordValues = {
             id: eventId,
         };
@@ -201,7 +201,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved when done.
      */
     async markDeleted(eventId: number, name: string, deleteAll?: boolean, siteId?: string): Promise<number> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const event: AddonCalendarOfflineDeletedEventDBRecord = {
             id: eventId,
             name: name || '',
@@ -227,7 +227,7 @@ export class AddonCalendarOfflineProvider {
         timeCreated?: number,
         siteId?: string,
     ): Promise<AddonCalendarOfflineEventDBRecord> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         timeCreated = timeCreated || Date.now();
         const event: AddonCalendarOfflineEventDBRecord = {
             id: eventId || -timeCreated,
@@ -263,7 +263,7 @@ export class AddonCalendarOfflineProvider {
      * @return Promise resolved if deleted, rejected if failure.
      */
     async unmarkDeleted(eventId: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const conditions: SQLiteDBRecordValues = {
             id: eventId,
         };
@@ -272,5 +272,4 @@ export class AddonCalendarOfflineProvider {
     }
 
 }
-export class AddonCalendarOffline extends makeSingleton(AddonCalendarOfflineProvider) {}
-
+export const AddonCalendarOffline = makeSingleton(AddonCalendarOfflineProvider);

src/addons/calendar/services/calendar-sync.ts

@@ -81,7 +81,7 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
      * @return Promise resolved when the events are synced or if it doesn't need to be synced.
      */
     async syncEventsIfNeeded(siteId?: string): Promise<AddonCalendarSyncEvents | undefined> {
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         const needed = await this.isSyncNeeded(AddonCalendarSyncProvider.SYNC_ID, siteId);
 
@@ -97,7 +97,7 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
      * @return Promise resolved if sync is successful, rejected otherwise.
      */
     async syncEvents(siteId?: string): Promise<AddonCalendarSyncEvents> {
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         if (this.isSyncing(AddonCalendarSyncProvider.SYNC_ID, siteId)) {
             // There's already a sync ongoing for this site, return the promise.
@@ -127,32 +127,32 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
             updated: false,
         };
 
-        const eventIds: number[] = await CoreUtils.instance.ignoreErrors(AddonCalendarOffline.instance.getAllEventsIds(siteId), []);
+        const eventIds: number[] = await CoreUtils.ignoreErrors(AddonCalendarOffline.getAllEventsIds(siteId), []);
 
         if (eventIds.length > 0) {
-            if (!CoreApp.instance.isOnline()) {
+            if (!CoreApp.isOnline()) {
                 // Cannot sync in offline.
                 throw new CoreNetworkError();
             }
 
             const promises = eventIds.map((eventId) => this.syncOfflineEvent(eventId, result, siteId));
 
-            await CoreUtils.instance.allPromises(promises);
+            await CoreUtils.allPromises(promises);
 
             if (result.updated) {
 
                 // Data has been sent to server. Now invalidate the WS calls.
                 const promises = [
-                    AddonCalendar.instance.invalidateEventsList(siteId),
-                    AddonCalendarHelper.instance.refreshAfterChangeEvents(result.toinvalidate, siteId),
+                    AddonCalendar.invalidateEventsList(siteId),
+                    AddonCalendarHelper.refreshAfterChangeEvents(result.toinvalidate, siteId),
                 ];
 
-                await CoreUtils.instance.ignoreErrors(Promise.all(promises));
+                await CoreUtils.ignoreErrors(Promise.all(promises));
             }
         }
 
         // Sync finished, set sync time.
-        await CoreUtils.instance.ignoreErrors(this.setSyncTime(AddonCalendarSyncProvider.SYNC_ID, siteId));
+        await CoreUtils.ignoreErrors(this.setSyncTime(AddonCalendarSyncProvider.SYNC_ID, siteId));
 
         // All done, return the result.
         return result;
@@ -169,21 +169,21 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
     protected async syncOfflineEvent(eventId: number, result: AddonCalendarSyncEvents, siteId?: string): Promise<void> {
 
         // Verify that event isn't blocked.
-        if (CoreSync.instance.isBlocked(AddonCalendarProvider.COMPONENT, eventId, siteId)) {
+        if (CoreSync.isBlocked(AddonCalendarProvider.COMPONENT, eventId, siteId)) {
             this.logger.debug('Cannot sync event ' + eventId + ' because it is blocked.');
 
-            throw new CoreSyncBlockedError(Translate.instance.instant(
+            throw new CoreSyncBlockedError(Translate.instant(
                 'core.errorsyncblocked',
-                { $a: Translate.instance.instant('addon.calendar.calendarevent') },
+                { $a: Translate.instant('addon.calendar.calendarevent') },
             ));
         }
 
         // First of all, check if the event has been deleted.
         try {
-            const data = await AddonCalendarOffline.instance.getDeletedEvent(eventId, siteId);
+            const data = await AddonCalendarOffline.getDeletedEvent(eventId, siteId);
             // Delete the event.
             try {
-                await AddonCalendar.instance.deleteEventOnline(data.id, !!data.repeat, siteId);
+                await AddonCalendar.deleteEventOnline(data.id, !!data.repeat, siteId);
 
                 result.updated = true;
                 result.deleted.push(eventId);
@@ -191,13 +191,13 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
                 // Event sent, delete the offline data.
                 const promises: Promise<void>[] = [];
 
-                promises.push(AddonCalendarOffline.instance.unmarkDeleted(eventId, siteId));
-                promises.push(AddonCalendarOffline.instance.deleteEvent(eventId, siteId).catch(() => {
+                promises.push(AddonCalendarOffline.unmarkDeleted(eventId, siteId));
+                promises.push(AddonCalendarOffline.deleteEvent(eventId, siteId).catch(() => {
                     // Ignore errors, maybe there was no edit data.
                 }));
 
                 // We need the event data to invalidate it. Get it from local DB.
-                promises.push(AddonCalendar.instance.getEventFromLocalDb(eventId, siteId).then((event) => {
+                promises.push(AddonCalendar.getEventFromLocalDb(eventId, siteId).then((event) => {
                     result.toinvalidate.push({
                         id: event.id,
                         repeatid: event.repeatid,
@@ -213,7 +213,7 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
                 await Promise.all(promises);
             } catch (error) {
 
-                if (!CoreUtils.instance.isWebServiceError(error)) {
+                if (!CoreUtils.isWebServiceError(error)) {
                     // Local error, reject.
                     throw error;
                 }
@@ -223,17 +223,17 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
 
                 const promises: Promise<void>[] = [];
 
-                promises.push(AddonCalendarOffline.instance.unmarkDeleted(eventId, siteId));
-                promises.push(AddonCalendarOffline.instance.deleteEvent(eventId, siteId).catch(() => {
+                promises.push(AddonCalendarOffline.unmarkDeleted(eventId, siteId));
+                promises.push(AddonCalendarOffline.deleteEvent(eventId, siteId).catch(() => {
                     // Ignore errors, maybe there was no edit data.
                 }));
 
                 await Promise.all(promises);
                 // Event deleted, add a warning.
-                result.warnings.push(Translate.instance.instant('core.warningofflinedatadeleted', {
-                    component: Translate.instance.instant('addon.calendar.calendarevent'),
+                result.warnings.push(Translate.instant('core.warningofflinedatadeleted', {
+                    component: Translate.instant('addon.calendar.calendarevent'),
                     name: data.name,
-                    error: CoreTextUtils.instance.getErrorMessageFromError(error),
+                    error: CoreTextUtils.getErrorMessageFromError(error),
                 }));
             }
 
@@ -243,11 +243,11 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
         }
 
         // Not deleted. Now get the event data.
-        const event = await AddonCalendarOffline.instance.getEvent(eventId, siteId);
+        const event = await AddonCalendarOffline.getEvent(eventId, siteId);
 
         // Try to send the data.
         const data: AddonCalendarSubmitCreateUpdateFormDataWSParams = Object.assign(
-            CoreUtils.instance.clone(event),
+            CoreUtils.clone(event),
             {
                 description: {
                     text: event.description || '',
@@ -257,7 +257,7 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
         ); // Clone the object because it will be modified in the submit function.
 
         try {
-            const newEvent = await AddonCalendar.instance.submitEventOnline(eventId > 0 ? eventId : 0, data, siteId);
+            const newEvent = await AddonCalendar.submitEventOnline(eventId > 0 ? eventId : 0, data, siteId);
 
             result.updated = true;
             result.events.push(newEvent);
@@ -274,10 +274,10 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
             });
 
             // Event sent, delete the offline data.
-            return AddonCalendarOffline.instance.deleteEvent(event.id!, siteId);
+            return AddonCalendarOffline.deleteEvent(event.id!, siteId);
 
         } catch (error) {
-            if (!CoreUtils.instance.isWebServiceError(error)) {
+            if (!CoreUtils.isWebServiceError(error)) {
                 // Local error, reject.
                 throw error;
             }
@@ -285,19 +285,19 @@ export class AddonCalendarSyncProvider extends CoreSyncBaseProvider<AddonCalenda
             // The WebService has thrown an error, this means that the event cannot be created. Delete it.
             result.updated = true;
 
-            await AddonCalendarOffline.instance.deleteEvent(event.id!, siteId);
+            await AddonCalendarOffline.deleteEvent(event.id!, siteId);
             // Event deleted, add a warning.
-            result.warnings.push(Translate.instance.instant('core.warningofflinedatadeleted', {
-                component: Translate.instance.instant('addon.calendar.calendarevent'),
+            result.warnings.push(Translate.instant('core.warningofflinedatadeleted', {
+                component: Translate.instant('addon.calendar.calendarevent'),
                 name: event.name,
-                error: CoreTextUtils.instance.getErrorMessageFromError(error),
+                error: CoreTextUtils.getErrorMessageFromError(error),
             }));
         }
     }
 
 }
 
-export class AddonCalendarSync extends makeSingleton(AddonCalendarSyncProvider) {}
+export const AddonCalendarSync = makeSingleton(AddonCalendarSyncProvider, ['component', 'syncInterval']);
 
 export type AddonCalendarSyncEvents = {
     warnings: string[];

src/addons/calendar/services/calendar.ts

@@ -113,7 +113,7 @@ export class AddonCalendarProvider {
      */
     async canDeleteEvents(siteId?: string): Promise<boolean> {
         try {
-            const site = await CoreSites.instance.getSite(siteId);
+            const site = await CoreSites.getSite(siteId);
 
             return this.canDeleteEventsInSite(site);
         } catch {
@@ -129,7 +129,7 @@ export class AddonCalendarProvider {
      * @since 3.3
      */
     canDeleteEventsInSite(site?: CoreSite): boolean {
-        site = site || CoreSites.instance.getCurrentSite();
+        site = site || CoreSites.getCurrentSite();
 
         return !!site?.wsAvailable('core_calendar_delete_calendar_events');
     }
@@ -143,7 +143,7 @@ export class AddonCalendarProvider {
      */
     async canEditEvents(siteId?: string): Promise<boolean> {
         try {
-            const site = await CoreSites.instance.getSite(siteId);
+            const site = await CoreSites.getSite(siteId);
 
             return this.canEditEventsInSite(site);
         } catch {
@@ -159,7 +159,7 @@ export class AddonCalendarProvider {
      * @since 3.7.1
      */
     canEditEventsInSite(site?: CoreSite): boolean {
-        site = site || CoreSites.instance.getCurrentSite();
+        site = site || CoreSites.getCurrentSite();
 
         // The WS to create/edit events requires a fix that was integrated in 3.7.1.
         return !!site?.isVersionGreaterEqualThan('3.7.1');
@@ -174,7 +174,7 @@ export class AddonCalendarProvider {
      */
     async canViewMonth(siteId?: string): Promise<boolean> {
         try {
-            const site = await CoreSites.instance.getSite(siteId);
+            const site = await CoreSites.getSite(siteId);
 
             return this.canViewMonthInSite(site);
         } catch {
@@ -190,7 +190,7 @@ export class AddonCalendarProvider {
      * @since 3.4
      */
     canViewMonthInSite(site?: CoreSite): boolean {
-        site = site || CoreSites.instance.getCurrentSite();
+        site = site || CoreSites.getCurrentSite();
 
         return !!site?.wsAvailable('core_calendar_get_calendar_monthly_view');
     }
@@ -212,7 +212,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when done.
      */
     async cleanExpiredEvents(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         if (this.canViewMonthInSite(site)) {
             // Site supports monthly view, don't clean expired events because user can see past events.
             return;
@@ -220,7 +220,7 @@ export class AddonCalendarProvider {
         const events = await site.getDb().getRecordsSelect<AddonCalendarEventDBRecord>(
             EVENTS_TABLE,
             'timestart + timeduration < ?',
-            [CoreTimeUtils.instance.timestamp()],
+            [CoreTimeUtils.timestamp()],
         );
 
         await Promise.all(events.map((event) => this.deleteLocalEvent(event.id!, siteId)));
@@ -244,25 +244,25 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<boolean> {
 
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         // Function to store the submission to be synchronized later.
         const storeOffline = (): Promise<boolean> =>
-            AddonCalendarOffline.instance.markDeleted(eventId, name, deleteAll, siteId).then(() => false);
+            AddonCalendarOffline.markDeleted(eventId, name, deleteAll, siteId).then(() => false);
 
-        if (forceOffline || !CoreApp.instance.isOnline()) {
+        if (forceOffline || !CoreApp.isOnline()) {
             // App is offline, store the action.
             return storeOffline();
         }
 
         // If the event is already stored, discard it first.
-        await AddonCalendarOffline.instance.unmarkDeleted(eventId, siteId);
+        await AddonCalendarOffline.unmarkDeleted(eventId, siteId);
         try {
             await this.deleteEventOnline(eventId, deleteAll, siteId);
 
             return true;
         } catch (error) {
-            if (error && !CoreUtils.instance.isWebServiceError(error)) {
+            if (error && !CoreUtils.isWebServiceError(error)) {
                 // Couldn't connect to server, store in offline.
                 return storeOffline();
             } else {
@@ -281,7 +281,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when done.
      */
     async deleteEventOnline(eventId: number, deleteAll = false, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const params: AddonCalendarDeleteCalendarEventsWSParams = {
             events: [
                 {
@@ -305,7 +305,7 @@ export class AddonCalendarProvider {
      * @return Resolved when done.
      */
     protected async deleteLocalEvent(eventId: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         siteId = site.getId();
 
         const promises: Promise<unknown>[] = [];
@@ -334,11 +334,11 @@ export class AddonCalendarProvider {
      */
     async initialize(): Promise<void> {
 
-        CoreLocalNotifications.instance.registerClick<AddonCalendarPushNotificationData>(
+        CoreLocalNotifications.registerClick<AddonCalendarPushNotificationData>(
             AddonCalendarProvider.COMPONENT,
             async (notification) => {
                 if (notification.eventId) {
-                    await ApplicationInit.instance.donePromise;
+                    await ApplicationInit.donePromise;
 
                     const disabled = await this.isDisabled(notification.siteId);
                     if (disabled) {
@@ -347,10 +347,10 @@ export class AddonCalendarProvider {
                     }
 
                     // Check which page we should load.
-                    const site = await CoreSites.instance.getSite(notification.siteId);
+                    const site = await CoreSites.getSite(notification.siteId);
                     const pageName = this.getMainCalendarPagePath(site);
 
-                    CoreNavigator.instance.navigateToSitePath(
+                    CoreNavigator.navigateToSitePath(
                         pageName,
                         { params: { eventId: notification.eventId }, siteId: notification.siteId },
                     );
@@ -389,16 +389,16 @@ export class AddonCalendarProvider {
             if (moment(start).isSame(end, 'day')) {
                 // Event starts and ends the same day.
                 if (event.timeduration == CoreConstants.SECONDS_DAY) {
-                    time = Translate.instance.instant('addon.calendar.allday');
+                    time = Translate.instant('addon.calendar.allday');
                 } else {
-                    time = CoreTimeUtils.instance.userDate(start, format) + ' <strong>&raquo;</strong> ' +
-                            CoreTimeUtils.instance.userDate(end, format);
+                    time = CoreTimeUtils.userDate(start, format) + ' <strong>&raquo;</strong> ' +
+                            CoreTimeUtils.userDate(end, format);
                 }
 
             } else {
                 // Event lasts more than one day.
-                const timeStart = CoreTimeUtils.instance.userDate(start, format);
-                const timeEnd = CoreTimeUtils.instance.userDate(end, format);
+                const timeStart = CoreTimeUtils.userDate(start, format);
+                const timeEnd = CoreTimeUtils.userDate(end, format);
                 const promises: Promise<void>[] = [];
 
                 // Don't use common words when the event lasts more than one day.
@@ -408,14 +408,14 @@ export class AddonCalendarProvider {
                 // Add links to the days if needed.
                 if (dayStart && (!seenDay || !moment(seenDay).isSame(start, 'day'))) {
                     promises.push(this.getViewUrl('day', event.timestart, undefined, siteId).then((url) => {
-                        dayStart = CoreUrlUtils.instance.buildLink(url, dayStart);
+                        dayStart = CoreUrlUtils.buildLink(url, dayStart);
 
                         return;
                     }));
                 }
                 if (dayEnd && (!seenDay || !moment(seenDay).isSame(end, 'day'))) {
                     promises.push(this.getViewUrl('day', end / 1000, undefined, siteId).then((url) => {
-                        dayEnd = CoreUrlUtils.instance.buildLink(url, dayEnd);
+                        dayEnd = CoreUrlUtils.buildLink(url, dayEnd);
 
                         return;
                     }));
@@ -427,7 +427,7 @@ export class AddonCalendarProvider {
             }
         } else {
             // There is no time duration.
-            time = CoreTimeUtils.instance.userDate(start, format);
+            time = CoreTimeUtils.userDate(start, format);
         }
 
         if (showTime) {
@@ -443,7 +443,7 @@ export class AddonCalendarProvider {
         // Add link to view the day.
         const url = await this.getViewUrl('day', event.timestart, undefined, siteId);
 
-        return CoreUrlUtils.instance.buildLink(url, this.getDayRepresentation(start, useCommonWords)) + ', ' + time;
+        return CoreUrlUtils.buildLink(url, this.getDayRepresentation(start, useCommonWords)) + ', ' + time;
     }
 
     /**
@@ -455,7 +455,7 @@ export class AddonCalendarProvider {
      * @since 3.7
      */
     async getAccessInformation(courseId?: number, siteId?: string): Promise<AddonCalendarGetCalendarAccessInformationWSResponse> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const params: AddonCalendarGetCalendarAccessInformationWSParams = {};
         const preSets: CoreSiteWSPreSets = {
             cacheKey: this.getAccessInformationCacheKey(courseId),
@@ -484,7 +484,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved with all the events.
      */
     async getAllEventsFromLocalDb(siteId?: string): Promise<AddonCalendarEventDBRecord[]> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return await site.getDb().getAllRecords(EVENTS_TABLE);
     }
@@ -498,7 +498,7 @@ export class AddonCalendarProvider {
      * @since 3.7
      */
     async getAllowedEventTypes(courseId?: number, siteId?: string): Promise<{[name: string]: boolean}> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const params: AddonCalendarGetAllowedEventTypesWSParams = {};
         const preSets: CoreSiteWSPreSets = {
             cacheKey: this.getAllowedEventTypesCacheKey(courseId),
@@ -537,10 +537,10 @@ export class AddonCalendarProvider {
      * @return Promise resolved with the look ahead (number of days).
      */
     async getCalendarLookAhead(siteId?: string): Promise<number> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         let value: string | undefined;
         try {
-            value = await CoreUser.instance.getUserPreference('calendar_lookahead');
+            value = await CoreUser.getUserPreference('calendar_lookahead');
         } catch {
             // Ignore errors.
         }
@@ -559,11 +559,11 @@ export class AddonCalendarProvider {
      * @return Promise resolved with the format.
      */
     async getCalendarTimeFormat(siteId?: string): Promise<string> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         let format: string | undefined;
 
         try {
-            format = await CoreUser.instance.getUserPreference('calendar_timeformat');
+            format = await CoreUser.getUserPreference('calendar_timeformat');
         } catch {
             // Ignore errors.
         }
@@ -573,12 +573,12 @@ export class AddonCalendarProvider {
         }
 
         if (format === AddonCalendarProvider.CALENDAR_TF_12) {
-            format = Translate.instance.instant('core.strftimetime12');
+            format = Translate.instant('core.strftimetime12');
         } else if (format === AddonCalendarProvider.CALENDAR_TF_24) {
-            format = Translate.instance.instant('core.strftimetime24');
+            format = Translate.instant('core.strftimetime24');
         }
 
-        return format && format !== '0' ? format : Translate.instance.instant('core.strftimetime');
+        return format && format !== '0' ? format : Translate.instant('core.strftimetime');
     }
 
     /**
@@ -592,23 +592,23 @@ export class AddonCalendarProvider {
 
         if (!useCommonWords) {
             // We don't want words, just a date.
-            return CoreTimeUtils.instance.userDate(time, 'core.strftimedayshort');
+            return CoreTimeUtils.userDate(time, 'core.strftimedayshort');
         }
 
         const date = moment(time);
         const today = moment();
 
         if (date.isSame(today, 'day')) {
-            return Translate.instance.instant('addon.calendar.today');
+            return Translate.instant('addon.calendar.today');
         }
         if (date.isSame(today.clone().subtract(1, 'days'), 'day')) {
-            return Translate.instance.instant('addon.calendar.yesterday');
+            return Translate.instant('addon.calendar.yesterday');
         }
         if (date.isSame(today.clone().add(1, 'days'), 'day')) {
-            return Translate.instance.instant('addon.calendar.tomorrow');
+            return Translate.instant('addon.calendar.tomorrow');
         }
 
-        return CoreTimeUtils.instance.userDate(time, 'core.strftimedayshort');
+        return CoreTimeUtils.userDate(time, 'core.strftimedayshort');
     }
 
     /**
@@ -618,11 +618,11 @@ export class AddonCalendarProvider {
      * @return Promise resolved with the default time.
      */
     async getDefaultNotificationTime(siteId?: string): Promise<number> {
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         const key = AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_SETTING + '#' + siteId;
 
-        return CoreConfig.instance.get(key, AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME);
+        return CoreConfig.get(key, AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME);
     }
 
     /**
@@ -633,7 +633,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the event data is retrieved.
      */
     async getEvent(id: number, siteId?: string): Promise<AddonCalendarGetEventsEvent | AddonCalendarEventBase> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const preSets: CoreSiteWSPreSets = {
             cacheKey: this.getEventCacheKey(id),
             updateFrequency: CoreSite.FREQUENCY_RARELY,
@@ -670,7 +670,7 @@ export class AddonCalendarProvider {
      * @since 3.4
      */
     async getEventById(id: number, siteId?: string): Promise<AddonCalendarEvent> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const preSets: CoreSiteWSPreSets = {
             cacheKey: this.getEventCacheKey(id),
             updateFrequency: CoreSite.FREQUENCY_RARELY,
@@ -710,7 +710,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the event data is retrieved.
      */
     async getEventFromLocalDb(id: number, siteId?: string): Promise<AddonCalendarGetEventsEvent | AddonCalendarEvent> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const record: AddonCalendarGetEventsEvent | AddonCalendarEvent | AddonCalendarEventDBRecord =
             await site.getDb().getRecord(EVENTS_TABLE, { id: id });
 
@@ -729,18 +729,18 @@ export class AddonCalendarProvider {
         eventConverted.iscategoryevent = originalEvent.eventtype == AddonCalendarEventType.CATEGORY;
         eventConverted.normalisedeventtype = this.getEventType(recordAsRecord);
         try {
-            eventConverted.category = CoreTextUtils.instance.parseJSON(recordAsRecord.category!);
+            eventConverted.category = CoreTextUtils.parseJSON(recordAsRecord.category!);
         } catch {
             // Ignore errors.
         }
 
         try {
-            eventConverted.course = CoreTextUtils.instance.parseJSON(recordAsRecord.course!);
+            eventConverted.course = CoreTextUtils.parseJSON(recordAsRecord.course!);
         } catch {
             // Ignore errors.
         }
         try {
-            eventConverted.subscription = CoreTextUtils.instance.parseJSON(recordAsRecord.subscription!);
+            eventConverted.subscription = CoreTextUtils.parseJSON(recordAsRecord.subscription!);
         } catch {
             // Ignore errors.
         }
@@ -761,7 +761,7 @@ export class AddonCalendarProvider {
         time: number,
         siteId?: string,
     ): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const reminder: AddonCalendarReminderDBRecord = {
             eventid: event.id,
             time: time,
@@ -794,10 +794,10 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the notification is updated.
      */
     async deleteEventReminder(id: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
-        if (CoreLocalNotifications.instance.isAvailable()) {
-            CoreLocalNotifications.instance.cancel(id, AddonCalendarProvider.COMPONENT, site.getId());
+        if (CoreLocalNotifications.isAvailable()) {
+            CoreLocalNotifications.cancel(id, AddonCalendarProvider.COMPONENT, site.getId());
         }
 
         await site.getDb().deleteRecords(REMINDERS_TABLE, { id: id });
@@ -825,7 +825,7 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<AddonCalendarCalendarDay> {
 
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const params: AddonCalendarGetCalendarDayViewWSParams = {
             year: year,
             month: month,
@@ -895,7 +895,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the event data is retrieved.
      */
     async getEventReminders(id: number, siteId?: string): Promise<AddonCalendarReminderDBRecord[]> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return await site.getDb().getRecords(REMINDERS_TABLE, { eventid: id }, 'time ASC');
     }
@@ -920,9 +920,9 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<AddonCalendarGetEventsEvent[]> {
 
-        initialTime = initialTime || CoreTimeUtils.instance.timestamp();
+        initialTime = initialTime || CoreTimeUtils.timestamp();
 
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         siteId = site.getId();
 
         const start = initialTime + (CoreConstants.SECONDS_DAY * daysToStart);
@@ -943,7 +943,7 @@ export class AddonCalendarProvider {
 
         const promises: Promise<void>[] = [];
 
-        promises.push(CoreCourses.instance.getUserCourses(false, siteId).then((courses) => {
+        promises.push(CoreCourses.getUserCourses(false, siteId).then((courses) => {
             params.events!.courseids = courses.map((course) => course.id);
             params.events!.courseids.push(site.getSiteHomeId()); // Add front page.
 
@@ -951,7 +951,7 @@ export class AddonCalendarProvider {
             return;
         }));
 
-        promises.push(CoreGroups.instance.getAllUserGroups(siteId).then((groups) => {
+        promises.push(CoreGroups.getAllUserGroups(siteId).then((groups) => {
             params.events!.groupids = groups.map((group) => group.id);
 
             return;
@@ -1004,7 +1004,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved with all the events.
      */
     async getLocalEventsByRepeatIdFromLocalDb(repeatId: number, siteId?: string): Promise<AddonCalendarEventDBRecord[]> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return await site.getDb().getRecords(EVENTS_TABLE, { repeatid: repeatId });
     }
@@ -1029,7 +1029,7 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<AddonCalendarMonth> {
 
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const params: AddonCalendarGetCalendarMonthlyViewWSParams = {
             year: year,
             month: month,
@@ -1063,8 +1063,8 @@ export class AddonCalendarProvider {
         });
 
         // Store starting week day preference, we need it in offline to show months that are not in cache.
-        if (CoreApp.instance.isOnline()) {
-            CoreConfig.instance.set(AddonCalendarProvider.STARTING_WEEK_DAY, response.daynames[0].dayno);
+        if (CoreApp.isOnline()) {
+            CoreConfig.set(AddonCalendarProvider.STARTING_WEEK_DAY, response.daynames[0].dayno);
         }
 
         return response;
@@ -1120,7 +1120,7 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<AddonCalendarUpcoming> {
 
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const params: AddonCalendarGetCalendarUpcomingViewWSParams = {};
         if (courseId) {
@@ -1177,8 +1177,8 @@ export class AddonCalendarProvider {
      * @return Promise resolved with the URL.x
      */
     async getViewUrl(view: string, time?: number, courseId?: string, siteId?: string): Promise<string> {
-        const site = await CoreSites.instance.getSite(siteId);
-        let url = CoreTextUtils.instance.concatenatePaths(site.getURL(), 'calendar/view.php?view=' + view);
+        const site = await CoreSites.getSite(siteId);
+        let url = CoreTextUtils.concatenatePaths(site.getURL(), 'calendar/view.php?view=' + view);
 
         if (time) {
             url += '&time=' + time;
@@ -1210,7 +1210,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateAccessInformation(courseId?: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKey(this.getAccessInformationCacheKey(courseId));
     }
@@ -1223,7 +1223,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateAllowedEventTypes(courseId?: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKey(this.getAllowedEventTypesCacheKey(courseId));
     }
@@ -1235,7 +1235,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateAllDayEvents(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getDayEventsPrefixCacheKey());
     }
@@ -1249,7 +1249,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateDayEvents(year: number, month: number, day: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getDayEventsDayPrefixCacheKey(year, month, day));
     }
@@ -1261,12 +1261,12 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the list is invalidated.
      */
     async invalidateEventsList(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         siteId = site.getId();
         const promises: Promise<void>[] = [];
-        promises.push(CoreCourses.instance.invalidateUserCourses(siteId));
-        promises.push(CoreGroups.instance.invalidateAllUserGroups(siteId));
+        promises.push(CoreCourses.invalidateUserCourses(siteId));
+        promises.push(CoreGroups.invalidateAllUserGroups(siteId));
         promises.push(site.invalidateWsCacheForKeyStartingWith(this.getEventsListPrefixCacheKey()));
 
         await Promise.all(promises);
@@ -1280,7 +1280,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the list is invalidated.
      */
     async invalidateEvent(eventId: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKey(this.getEventCacheKey(eventId));
     }
@@ -1292,7 +1292,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateAllMonthlyEvents(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getMonthlyEventsPrefixCacheKey());
     }
@@ -1305,7 +1305,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateMonthlyEvents(year: number, month: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getMonthlyEventsMonthPrefixCacheKey(year, month));
     }
@@ -1317,7 +1317,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateAllUpcomingEvents(siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getUpcomingEventsPrefixCacheKey());
     }
@@ -1331,7 +1331,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateUpcomingEvents(courseId?: number, categoryId?: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         await site.invalidateWsCacheForKeyStartingWith(this.getUpcomingEventsCacheKey(courseId, categoryId));
     }
@@ -1343,7 +1343,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     async invalidateLookAhead(siteId?: string): Promise<void> {
-        await CoreUser.instance.invalidateUserPreference('calendar_lookahead', siteId);
+        await CoreUser.invalidateUserPreference('calendar_lookahead', siteId);
     }
 
     /**
@@ -1353,7 +1353,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when the data is invalidated.
      */
     invalidateTimeFormat(siteId?: string): Promise<void> {
-        return CoreUser.instance.invalidateUserPreference('calendar_timeformat', siteId);
+        return CoreUser.invalidateUserPreference('calendar_timeformat', siteId);
     }
 
     /**
@@ -1363,7 +1363,7 @@ export class AddonCalendarProvider {
      * @return Whether it's disabled.
      */
     isCalendarDisabledInSite(site?: CoreSite): boolean {
-        site = site || CoreSites.instance.getCurrentSite();
+        site = site || CoreSites.getCurrentSite();
 
         return !!site?.isFeatureDisabled('CoreMainMenuDelegate_AddonCalendar');
     }
@@ -1375,7 +1375,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved with true if disabled, rejected or resolved with false otherwise.
      */
     async isDisabled(siteId?: string): Promise<boolean> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         return this.isCalendarDisabledInSite(site);
     }
@@ -1389,7 +1389,7 @@ export class AddonCalendarProvider {
      */
     async isGetEventByIdAvailable(siteId?: string): Promise<boolean> {
         try {
-            const site = await CoreSites.instance.getSite(siteId);
+            const site = await CoreSites.getSite(siteId);
 
             return this.isGetEventByIdAvailableInSite(site);
         } catch {
@@ -1405,7 +1405,7 @@ export class AddonCalendarProvider {
      * @since 3.4
      */
     isGetEventByIdAvailableInSite(site?: CoreSite): boolean {
-        site = site || CoreSites.instance.getCurrentSite();
+        site = site || CoreSites.getCurrentSite();
 
         return !!site?.wsAvailable('core_calendar_get_calendar_event_by_id');
     }
@@ -1418,11 +1418,11 @@ export class AddonCalendarProvider {
      * @return Promise resolved when all the notifications have been scheduled.
      */
     async scheduleAllSitesEventsNotifications(): Promise<void> {
-        await Platform.instance.ready();
+        await Platform.ready();
 
-        const notificationsEnabled = CoreLocalNotifications.instance.isAvailable();
+        const notificationsEnabled = CoreLocalNotifications.isAvailable();
 
-        const siteIds = await CoreSites.instance.getSitesIds();
+        const siteIds = await CoreSites.getSitesIds();
 
         const promises = siteIds.map((siteId: string) => this.cleanExpiredEvents(siteId).then(async() => {
             if (notificationsEnabled) {
@@ -1458,15 +1458,15 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<void> {
 
-        if (!CoreLocalNotifications.instance.isAvailable()) {
+        if (!CoreLocalNotifications.isAvailable()) {
             return;
         }
 
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         if (time === 0) {
             // Cancel if it was scheduled.
-            return CoreLocalNotifications.instance.cancel(reminderId, AddonCalendarProvider.COMPONENT, siteId);
+            return CoreLocalNotifications.cancel(reminderId, AddonCalendarProvider.COMPONENT, siteId);
         }
 
         if (time == -1) {
@@ -1475,7 +1475,7 @@ export class AddonCalendarProvider {
 
             if (time == 0) {
                 // Default notification time is disabled, do not show.
-                return CoreLocalNotifications.instance.cancel(reminderId, AddonCalendarProvider.COMPONENT, siteId);
+                return CoreLocalNotifications.cancel(reminderId, AddonCalendarProvider.COMPONENT, siteId);
             }
 
             time = event.timestart - (time * 60);
@@ -1485,7 +1485,7 @@ export class AddonCalendarProvider {
 
         if (time <= Date.now()) {
             // This reminder is over, don't schedule. Cancel if it was scheduled.
-            return CoreLocalNotifications.instance.cancel(reminderId, AddonCalendarProvider.COMPONENT, siteId);
+            return CoreLocalNotifications.cancel(reminderId, AddonCalendarProvider.COMPONENT, siteId);
         }
 
         const notificationData: AddonCalendarPushNotificationData = {
@@ -1497,7 +1497,7 @@ export class AddonCalendarProvider {
         const notification: ILocalNotification = {
             id: reminderId,
             title: event.name,
-            text: CoreTimeUtils.instance.userDate(event.timestart * 1000, 'core.strftimedaydatetime', true),
+            text: CoreTimeUtils.userDate(event.timestart * 1000, 'core.strftimedaydatetime', true),
             icon: 'file://assets/img/icons/calendar.png',
             trigger: {
                 at: new Date(time),
@@ -1505,7 +1505,7 @@ export class AddonCalendarProvider {
             data: notificationData,
         };
 
-        return CoreLocalNotifications.instance.schedule(notification, AddonCalendarProvider.COMPONENT, siteId);
+        return CoreLocalNotifications.schedule(notification, AddonCalendarProvider.COMPONENT, siteId);
     }
 
     /**
@@ -1522,11 +1522,11 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<void> {
 
-        if (!CoreLocalNotifications.instance.isAvailable()) {
+        if (!CoreLocalNotifications.isAvailable()) {
             return;
         }
 
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         const promises = events.map(async (event) => {
             const timeEnd = (event.timestart + event.timeduration) * 1000;
@@ -1555,11 +1555,11 @@ export class AddonCalendarProvider {
      * @return Promise resolved when stored.
      */
     async setDefaultNotificationTime(time: number, siteId?: string): Promise<void> {
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         const key = AddonCalendarProvider.DEFAULT_NOTIFICATION_TIME_SETTING + '#' + siteId;
 
-        await CoreConfig.instance.set(key, time);
+        await CoreConfig.set(key, time);
     }
 
     /**
@@ -1570,7 +1570,7 @@ export class AddonCalendarProvider {
      * @return Promise resolved when stored.
      */
     async storeEventInLocalDb(event:  AddonCalendarGetEventsEvent | AddonCalendarCalendarEvent, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         siteId = site.getId();
         try {
             await this.getEventFromLocalDb(event.id, site.id);
@@ -1646,7 +1646,7 @@ export class AddonCalendarProvider {
         events: (AddonCalendarGetEventsEvent | AddonCalendarCalendarEvent)[],
         siteId?: string,
     ): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         siteId = site.getId();
 
         await Promise.all(events.map((event: AddonCalendarGetEventsEvent| AddonCalendarCalendarEvent) =>
@@ -1672,28 +1672,28 @@ export class AddonCalendarProvider {
         siteId?: string,
     ): Promise<{sent: boolean; event: AddonCalendarOfflineEventDBRecord | AddonCalendarEvent}> {
 
-        siteId = siteId || CoreSites.instance.getCurrentSiteId();
+        siteId = siteId || CoreSites.getCurrentSiteId();
 
         // Function to store the event to be synchronized later.
         const storeOffline = (): Promise<{ sent: boolean; event: AddonCalendarOfflineEventDBRecord }> =>
-            AddonCalendarOffline.instance.saveEvent(eventId, formData, timeCreated, siteId).then((event) =>
+            AddonCalendarOffline.saveEvent(eventId, formData, timeCreated, siteId).then((event) =>
                 ({ sent: false, event }));
 
-        if (forceOffline || !CoreApp.instance.isOnline()) {
+        if (forceOffline || !CoreApp.isOnline()) {
             // App is offline, store the event.
             return storeOffline();
         }
 
         if (eventId) {
             // If the event is already stored, discard it first.
-            await AddonCalendarOffline.instance.deleteEvent(eventId, siteId);
+            await AddonCalendarOffline.deleteEvent(eventId, siteId);
         }
         try {
             const event = await this.submitEventOnline(eventId, formData, siteId);
 
             return ({ sent: true, event });
         } catch (error) {
-            if (error && !CoreUtils.instance.isWebServiceError(error)) {
+            if (error && !CoreUtils.isWebServiceError(error)) {
                 // Couldn't connect to server, store in offline.
                 return storeOffline();
             } else {
@@ -1716,7 +1716,7 @@ export class AddonCalendarProvider {
         formData: AddonCalendarSubmitCreateUpdateFormDataWSParams,
         siteId?: string,
     ): Promise<AddonCalendarEvent> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         // Add data that is "hidden" in web.
         formData.id = eventId;
         formData.userid = site.getUserId();
@@ -1728,14 +1728,14 @@ export class AddonCalendarProvider {
             formData['_qf__core_calendar_local_event_forms_create'] = 1;
         }
         const params: AddonCalendarSubmitCreateUpdateFormWSParams = {
-            formdata: CoreUtils.instance.objectToGetParams(formData),
+            formdata: CoreUtils.objectToGetParams(formData),
         };
         const result =
             await site.write<AddonCalendarSubmitCreateUpdateFormWSResponse>('core_calendar_submit_create_update_form', params);
         if (result.validationerror) {
             // Simulate a WS error.
             throw new CoreWSError({
-                message: Translate.instance.instant('core.invalidformdata'),
+                message: Translate.instant('core.invalidformdata'),
                 errorcode: 'validationerror',
             });
         }
@@ -1745,7 +1745,7 @@ export class AddonCalendarProvider {
 
 }
 
-export class AddonCalendar extends makeSingleton(AddonCalendarProvider) {}
+export const AddonCalendar = makeSingleton(AddonCalendarProvider);
 
 /**
  * Data returned by calendar's events_exporter.

src/addons/calendar/services/handlers/mainmenu.ts

@@ -35,7 +35,7 @@ export class AddonCalendarMainMenuHandlerService implements CoreMainMenuHandler
      * @return Whether or not the handler is enabled on a site level.
      */
     async isEnabled(): Promise<boolean> {
-        return !AddonCalendar.instance.isCalendarDisabledInSite();
+        return !AddonCalendar.isCalendarDisabledInSite();
     }
 
     /**
@@ -47,11 +47,11 @@ export class AddonCalendarMainMenuHandlerService implements CoreMainMenuHandler
         return {
             icon: 'far-calendar',
             title: 'addon.calendar.calendar',
-            page: AddonCalendar.instance.getMainCalendarPagePath(),
+            page: AddonCalendar.getMainCalendarPagePath(),
             class: 'addon-calendar-handler',
         };
     }
 
 }
 
-export class AddonCalendarMainMenuHandler extends makeSingleton(AddonCalendarMainMenuHandlerService) {}
+export const AddonCalendarMainMenuHandler = makeSingleton(AddonCalendarMainMenuHandlerService);

src/addons/calendar/services/handlers/sync-cron.ts

@@ -34,7 +34,7 @@ export class AddonCalendarSyncCronHandlerService implements CoreCronHandler {
      * @return Promise resolved when done, rejected if failure.
      */
     async execute(siteId?: string, force?: boolean): Promise<void> {
-        await AddonCalendarSync.instance.syncAllEvents(siteId, force);
+        await AddonCalendarSync.syncAllEvents(siteId, force);
     }
 
     /**
@@ -43,9 +43,9 @@ export class AddonCalendarSyncCronHandlerService implements CoreCronHandler {
      * @return Time between consecutive executions (in ms).
      */
     getInterval(): number {
-        return AddonCalendarSync.instance.syncInterval;
+        return AddonCalendarSync.syncInterval;
     }
 
 }
 
-export class AddonCalendarSyncCronHandler extends makeSingleton(AddonCalendarSyncCronHandlerService) {}
+export const AddonCalendarSyncCronHandler = makeSingleton(AddonCalendarSyncCronHandlerService);

src/addons/calendar/services/handlers/view-link.ts

@@ -59,7 +59,7 @@ export class AddonCalendarViewLinkHandlerService extends CoreContentLinksHandler
                     stateParams.month = date.getMonth() + 1;
 
                     // @todo: Add checkMenu param.
-                    CoreNavigator.instance.navigateToSitePath('/calendar/index', { params: stateParams, siteId });
+                    CoreNavigator.navigateToSitePath('/calendar/index', { params: stateParams, siteId });
 
                 } else if (params.view == 'day') {
                     // Daily view, open the page.
@@ -73,7 +73,7 @@ export class AddonCalendarViewLinkHandlerService extends CoreContentLinksHandler
                     stateParams.month = date.getMonth() + 1;
                     stateParams.day = date.getDate();
 
-                    CoreNavigator.instance.navigateToSitePath('/calendar/day', { params: stateParams, siteId });
+                    CoreNavigator.navigateToSitePath('/calendar/day', { params: stateParams, siteId });
 
                 } else if (params.view == 'upcoming' || params.view == 'upcoming_mini') {
                     // Upcoming view, open the calendar tab.
@@ -83,7 +83,7 @@ export class AddonCalendarViewLinkHandlerService extends CoreContentLinksHandler
                     };
 
                     // @todo: Add checkMenu param.
-                    CoreNavigator.instance.navigateToSitePath('/calendar/index', { params: stateParams, siteId });
+                    CoreNavigator.navigateToSitePath('/calendar/index', { params: stateParams, siteId });
 
                 }
             },
@@ -105,15 +105,15 @@ export class AddonCalendarViewLinkHandlerService extends CoreContentLinksHandler
             return false;
         }
 
-        return AddonCalendar.instance.isDisabled(siteId).then((disabled) => {
+        return AddonCalendar.isDisabled(siteId).then((disabled) => {
             if (disabled) {
                 return false;
             }
 
-            return AddonCalendar.instance.canViewMonth(siteId);
+            return AddonCalendar.canViewMonth(siteId);
         });
     }
 
 }
 
-export class AddonCalendarViewLinkHandler extends makeSingleton(AddonCalendarViewLinkHandlerService) {}
+export const AddonCalendarViewLinkHandler = makeSingleton(AddonCalendarViewLinkHandlerService);

src/addons/coursecompletion/services/coursecompletion.ts

@@ -45,7 +45,7 @@ export class AddonCourseCompletionProvider {
      * @return True if user can mark course as self completed, false otherwise.
      */
     canMarkSelfCompleted(userId: number, completion: AddonCourseCompletionCourseCompletionStatus): boolean {
-        if (CoreSites.instance.getCurrentSiteUserId() != userId) {
+        if (CoreSites.getCurrentSiteUserId() != userId) {
             return false;
         }
 
@@ -100,7 +100,7 @@ export class AddonCourseCompletionProvider {
         siteId?: string,
     ): Promise<AddonCourseCompletionCourseCompletionStatus> {
 
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         userId = userId || site.getUserId();
         this.logger.debug('Get completion for course ' + courseId + ' and user ' + userId);
 
@@ -142,7 +142,7 @@ export class AddonCourseCompletionProvider {
      * @return Promise resolved when the list is invalidated.
      */
     async invalidateCourseCompletion(courseId: number, userId?: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         userId = userId || site.getUserId();
 
         await site.invalidateWsCacheForKey(this.getCompletionCacheKey(courseId, userId));
@@ -154,7 +154,7 @@ export class AddonCourseCompletionProvider {
      * @return True if plugin enabled, false otherwise.
      */
     isPluginViewEnabled(): boolean {
-        return CoreSites.instance.isLoggedIn();
+        return CoreSites.isLoggedIn();
     }
 
     /**
@@ -169,7 +169,7 @@ export class AddonCourseCompletionProvider {
             throw new CoreError('No courseId provided');
         }
 
-        const course = await CoreCourses.instance.getUserCourse(courseId, preferCache);
+        const course = await CoreCourses.getUserCourse(courseId, preferCache);
 
         if (course) {
             if (typeof course.enablecompletion != 'undefined' && !course.enablecompletion) {
@@ -195,14 +195,14 @@ export class AddonCourseCompletionProvider {
      * @return Promise resolved with true if plugin is enabled, rejected or resolved with false otherwise.
      */
     async isPluginViewEnabledForUser(courseId: number, userId?: number, siteId?: string): Promise<boolean> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
         const currentUserId = site.getUserId();
 
         // Check if user wants to view his own completion.
         try {
             if (!userId || userId == currentUserId) {
                 // Viewing own completion. Get the course to check if it has completion criteria.
-                const course = await CoreCourses.instance.getUserCourse(courseId, true);
+                const course = await CoreCourses.getUserCourse(courseId, true);
 
                 // If the site is returning the completionhascriteria then the user can view his own completion.
                 // We already checked the value in isPluginViewEnabledForCourse.
@@ -226,7 +226,7 @@ export class AddonCourseCompletionProvider {
 
             return true;
         } catch (error) {
-            if (CoreUtils.instance.isWebServiceError(error)) {
+            if (CoreUtils.isWebServiceError(error)) {
                 // The WS returned an error, plugin is not enabled.
                 return false;
             }
@@ -252,7 +252,7 @@ export class AddonCourseCompletionProvider {
      * @return Promise resolved on success.
      */
     async markCourseAsSelfCompleted(courseId: number, siteId?: string): Promise<void> {
-        const site = await CoreSites.instance.getSite(siteId);
+        const site = await CoreSites.getSite(siteId);
 
         const params: AddonCourseCompletionMarkCourseSelfCompletedWSParams = {
             courseid: courseId,
@@ -267,7 +267,7 @@ export class AddonCourseCompletionProvider {
 
 }
 
-export class AddonCourseCompletion extends makeSingleton(AddonCourseCompletionProvider) {}
+export const AddonCourseCompletion = makeSingleton(AddonCourseCompletionProvider);
 
 /**
  * Completion status returned by core_completion_get_course_completion_status.

src/addons/filter/activitynames/activitynames.module.ts

@@ -27,7 +27,7 @@ import { AddonFilterActivityNamesHandler } from './services/handlers/activitynam
             provide: APP_INITIALIZER,
             multi: true,
             deps: [],
-            useFactory: () => () => CoreFilterDelegate.instance.registerHandler(AddonFilterActivityNamesHandler.instance),
+            useFactory: () => () => CoreFilterDelegate.registerHandler(AddonFilterActivityNamesHandler.instance),
         },
     ],
 })

src/addons/filter/activitynames/services/handlers/activitynames.ts

@@ -43,4 +43,4 @@ export class AddonFilterActivityNamesHandlerService extends CoreFilterDefaultHan
 
 }
 
-export class AddonFilterActivityNamesHandler extends makeSingleton(AddonFilterActivityNamesHandlerService) {}
+export const AddonFilterActivityNamesHandler = makeSingleton(AddonFilterActivityNamesHandlerService);

src/addons/filter/algebra/algebra.module.ts

@@ -27,7 +27,7 @@ import { AddonFilterAlgebraHandler } from './services/handlers/algebra';
             provide: APP_INITIALIZER,
             multi: true,
             deps: [],
-            useFactory: () => () => CoreFilterDelegate.instance.registerHandler(AddonFilterAlgebraHandler.instance),
+            useFactory: () => () => CoreFilterDelegate.registerHandler(AddonFilterAlgebraHandler.instance),
         },
     ],
 })

src/addons/filter/algebra/services/handlers/algebra.ts

@@ -43,4 +43,4 @@ export class AddonFilterAlgebraHandlerService extends CoreFilterDefaultHandler {
 
 }
 
-export class AddonFilterAlgebraHandler extends makeSingleton(AddonFilterAlgebraHandlerService) {}
+export const AddonFilterAlgebraHandler = makeSingleton(AddonFilterAlgebraHandlerService);

src/addons/filter/censor/censor.module.ts

@@ -27,7 +27,7 @@ import { AddonFilterCensorHandler } from './services/handlers/censor';
             provide: APP_INITIALIZER,
             multi: true,
             deps: [],
-            useFactory: () => () => CoreFilterDelegate.instance.registerHandler(AddonFilterCensorHandler.instance),
+            useFactory: () => () => CoreFilterDelegate.registerHandler(AddonFilterCensorHandler.instance),
         },
     ],
 })

src/addons/filter/censor/services/handlers/censor.ts

@@ -43,4 +43,4 @@ export class AddonFilterCensorHandlerService extends CoreFilterDefaultHandler {
 
 }
 
-export class AddonFilterCensorHandler extends makeSingleton(AddonFilterCensorHandlerService) {}
+export const AddonFilterCensorHandler = makeSingleton(AddonFilterCensorHandlerService);

src/addons/filter/data/data.module.ts

@@ -27,7 +27,7 @@ import { AddonFilterDataHandler } from './services/handlers/data';
             provide: APP_INITIALIZER,
             multi: true,
             deps: [],
-            useFactory: () => () => CoreFilterDelegate.instance.registerHandler(AddonFilterDataHandler.instance),
+            useFactory: () => () => CoreFilterDelegate.registerHandler(AddonFilterDataHandler.instance),
         },
     ],
 })

src/addons/filter/data/services/handlers/data.ts

@@ -43,4 +43,4 @@ export class AddonFilterDataHandlerService extends CoreFilterDefaultHandler {
 
 }
 
-export class AddonFilterDataHandler extends makeSingleton(AddonFilterDataHandlerService) {}
+export const AddonFilterDataHandler = makeSingleton(AddonFilterDataHandlerService);

src/addons/filter/displayh5p/displayh5p.module.ts

@@ -27,7 +27,7 @@ import { AddonFilterDisplayH5PHandler } from './services/handlers/displayh5p';
             provide: APP_INITIALIZER,
             multi: true,
             deps: [],
-            useFactory: () => () => CoreFilterDelegate.instance.registerHandler(AddonFilterDisplayH5PHandler.instance),
+            useFactory: () => () => CoreFilterDelegate.registerHandler(AddonFilterDisplayH5PHandler.instance),
         },
     ],
 })

src/addons/filter/displayh5p/services/handlers/displayh5p.ts

@@ -109,4 +109,4 @@ export class AddonFilterDisplayH5PHandlerService extends CoreFilterDefaultHandle
 
 }
 
-export class AddonFilterDisplayH5PHandler extends makeSingleton(AddonFilterDisplayH5PHandlerService) {}
+export const AddonFilterDisplayH5PHandler = makeSingleton(AddonFilterDisplayH5PHandlerService);