diff --git a/src/app/app.component.ts b/src/app/app.component.ts
index fb53313e6..0e425823a 100644
--- a/src/app/app.component.ts
+++ b/src/app/app.component.ts
@@ -64,6 +64,9 @@ export class MoodleMobileApp implements OnInit {
 
             // Unload lang custom strings.
             this.langProvider.clearCustomStrings();
+
+            // Remove version classes from body.
+            this.removeVersionClass();
         });
 
         // Listen for session expired events.
@@ -144,6 +147,10 @@ export class MoodleMobileApp implements OnInit {
         this.eventsProvider.on(CoreEventsProvider.SITE_UPDATED, (data) => {
             if (data.siteId == this.sitesProvider.getCurrentSiteId()) {
                 loadCustomStrings();
+
+                // Add version classes to body.
+                this.removeVersionClass();
+                this.addVersionClass(this.sitesProvider.getReleaseNumber(data.release || ''));
             }
         });
 
@@ -190,4 +197,36 @@ export class MoodleMobileApp implements OnInit {
             }
         );
     }
+
+    /**
+     * Convenience function to add version to body classes.
+     *
+     * @param {string} release Current release number of the site.
+     */
+    protected addVersionClass(release: string): void {
+        const parts = release.split('.');
+
+        parts[1] = parts[1] || '0';
+        parts[2] = parts[2] || '0';
+
+        document.body.classList.add('version-' + parts[0], 'version-' + parts[0] + '-' + parts[1],
+            'version-' + parts[0] + '-' + parts[1] + '-' + parts[2]);
+
+    }
+
+    /**
+     * Convenience function to remove all version classes form body.
+     */
+    protected removeVersionClass(): void {
+        const remove = [];
+        Array.from(document.body.classList).forEach((tempClass) => {
+            if (tempClass.substring(0, 8) == 'version-') {
+                remove.push(tempClass);
+            }
+        });
+
+        remove.forEach((tempClass) => {
+            document.body.classList.remove(tempClass);
+        });
+    }
 }
diff --git a/src/core/courses/components/course-progress/course-progress.scss b/src/core/courses/components/course-progress/course-progress.scss
index ae2f1a1bd..4f2c29f5d 100644
--- a/src/core/courses/components/course-progress/course-progress.scss
+++ b/src/core/courses/components/course-progress/course-progress.scss
@@ -83,3 +83,7 @@ ion-app.app-root core-courses-course-progress {
         z-index: 1;
     }
 }
+
+body.version-3-1 .core-course-thumb{
+    display: none;
+}
diff --git a/src/providers/sites.ts b/src/providers/sites.ts
index 2a2fd1f99..27e088ef8 100644
--- a/src/providers/sites.ts
+++ b/src/providers/sites.ts
@@ -586,16 +586,13 @@ export class CoreSitesProvider {
         }
 
         // We couldn't validate by version number. Let's try to validate by release number.
-        if (info.release) {
-            const matches = info.release.match(/^([\d|\.]*)/);
-            if (matches && matches.length > 1) {
-                if (matches[1] >= release31) {
-                    return this.VALID_VERSION;
-                } else if (matches[1] >= release24) {
-                    return this.LEGACY_APP_VERSION;
-                } else {
-                    return this.INVALID_VERSION;
-                }
+        const release = this.getReleaseNumber(info.release || '');
+        if (release) {
+            if (release >= release31) {
+                return this.VALID_VERSION;
+            }
+            if (release >= release24) {
+                return this.LEGACY_APP_VERSION;
             }
         }
 
@@ -603,6 +600,21 @@ export class CoreSitesProvider {
         return this.INVALID_VERSION;
     }
 
+    /**
+     * Returns the release number from site release info.
+     *
+     * @param  {string}  rawRelease Raw release info text.
+     * @return {string}   Release number or empty.
+     */
+    getReleaseNumber(rawRelease: string): string {
+        const matches = rawRelease.match(/^\d(\.\d(\.\d+)?)?/);
+        if (matches) {
+            return matches[0];
+        }
+
+        return '';
+    }
+
     /**
      * Check if site info is valid. If it's not, return error message.
      *
@@ -1088,7 +1100,7 @@ export class CoreSitesProvider {
                     }
 
                     return this.appDB.updateRecords(this.SITES_TABLE, newValues, { id: siteId }).finally(() => {
-                        this.eventsProvider.trigger(CoreEventsProvider.SITE_UPDATED, {}, siteId);
+                        this.eventsProvider.trigger(CoreEventsProvider.SITE_UPDATED, info, siteId);
                     });
                 });
             });