diff --git a/src/core/directives/collapsible-footer.ts b/src/core/directives/collapsible-footer.ts
index 4a44fa0b9..73e9dbd5a 100644
--- a/src/core/directives/collapsible-footer.ts
+++ b/src/core/directives/collapsible-footer.ts
@@ -50,11 +50,10 @@ export class CoreCollapsibleFooterDirective implements OnInit, OnDestroy {
     protected contentScrollListener?: EventListener;
     protected endContentScrollListener?: EventListener;
     protected resizeListener?: CoreEventObserver;
-    protected domPromise?: CoreCancellablePromise<void>;
+    protected slotPromise?: CoreCancellablePromise<void>;
 
     constructor(el: ElementRef, protected ionContent: IonContent) {
         this.element = el.nativeElement;
-        this.element.setAttribute('slot', 'fixed'); // Just in case somebody forgets to add it.
     }
 
     /**
@@ -63,9 +62,9 @@ export class CoreCollapsibleFooterDirective implements OnInit, OnDestroy {
     async ngOnInit(): Promise<void> {
         // Only if not present or explicitly falsy it will be false.
         this.appearOnBottom = !CoreUtils.isFalseOrZero(this.appearOnBottom);
-        this.domPromise = CoreDom.waitToBeInDOM(this.element);
+        this.slotPromise = CoreDom.slotOnContent(this.element);
 
-        await this.domPromise;
+        await this.slotPromise;
         await this.waitLoadingsDone();
         await this.waitFormatTextsRendered();
 
@@ -229,7 +228,7 @@ export class CoreCollapsibleFooterDirective implements OnInit, OnDestroy {
         }
 
         this.resizeListener?.off();
-        this.domPromise?.cancel();
+        this.slotPromise?.cancel();
     }
 
 }
diff --git a/src/core/directives/fab.ts b/src/core/directives/fab.ts
index 90f700fc5..fe18f8274 100644
--- a/src/core/directives/fab.ts
+++ b/src/core/directives/fab.ts
@@ -31,19 +31,18 @@ export class CoreFabDirective implements OnInit, OnDestroy {
     protected element: HTMLElement;
     protected content?: HTMLIonContentElement | null;
     protected initialPaddingBottom = 0;
-    protected domPromise?: CoreCancellablePromise<void>;
+    protected slotPromise?: CoreCancellablePromise<void>;
 
     constructor(el: ElementRef) {
         this.element = el.nativeElement;
-        this.element.setAttribute('slot', 'fixed');
     }
 
     /**
      * @inheritdoc
      */
     async ngOnInit(): Promise<void> {
-        this.domPromise = CoreDom.waitToBeInDOM(this.element);
-        await this.domPromise;
+        this.slotPromise = CoreDom.slotOnContent(this.element);
+        await this.slotPromise;
 
         this.content = this.element.closest('ion-content');
 
@@ -70,12 +69,6 @@ export class CoreFabDirective implements OnInit, OnDestroy {
         }
 
         const initialHeight = this.element.getBoundingClientRect().height || 56;
-
-        // Move element to the nearest ion-content if it's not the parent
-        if (this.element.parentElement?.nodeName != 'ION-CONTENT') {
-            this.content.appendChild(this.element);
-        }
-
         this.content.style.setProperty('--padding-bottom', this.initialPaddingBottom + initialHeight + 'px');
     }
 
@@ -86,7 +79,7 @@ export class CoreFabDirective implements OnInit, OnDestroy {
         if (this.content) {
             this.content.style.setProperty('--padding-bottom', this.initialPaddingBottom + 'px');
         }
-        this.domPromise?.cancel();
+        this.slotPromise?.cancel();
     }
 
 }
diff --git a/src/core/features/block/components/side-blocks-button/side-blocks-button.ts b/src/core/features/block/components/side-blocks-button/side-blocks-button.ts
index e8b369c29..e748b67aa 100644
--- a/src/core/features/block/components/side-blocks-button/side-blocks-button.ts
+++ b/src/core/features/block/components/side-blocks-button/side-blocks-button.ts
@@ -12,9 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, ElementRef, Input, ViewChild } from '@angular/core';
+import { Component, ElementRef, Input, OnDestroy, OnInit, ViewChild } from '@angular/core';
+import { CoreCancellablePromise } from '@classes/cancellable-promise';
 import { CoreUserTours, CoreUserToursAlignment, CoreUserToursSide } from '@features/usertours/services/user-tours';
 import { CoreDomUtils } from '@services/utils/dom';
+import { CoreDom } from '@singletons/dom';
 import { CoreBlockSideBlocksTourComponent } from '../side-blocks-tour/side-blocks-tour';
 import { CoreBlockSideBlocksComponent } from '../side-blocks/side-blocks';
 
@@ -26,11 +28,25 @@ import { CoreBlockSideBlocksComponent } from '../side-blocks/side-blocks';
     templateUrl: 'side-blocks-button.html',
     styleUrls: ['side-blocks-button.scss'],
 })
-export class CoreBlockSideBlocksButtonComponent {
+export class CoreBlockSideBlocksButtonComponent implements OnInit, OnDestroy {
 
     @Input() courseId!: number;
     @ViewChild('button', { read: ElementRef }) button?: ElementRef<HTMLElement>;
 
+    protected element: HTMLElement;
+    protected slotPromise?: CoreCancellablePromise<void>;
+
+    constructor(el: ElementRef) {
+        this.element = el.nativeElement;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    async ngOnInit(): Promise<void> {
+        this.slotPromise = CoreDom.slotOnContent(this.element);
+    }
+
     /**
      * Open side blocks.
      */
@@ -62,4 +78,11 @@ export class CoreBlockSideBlocksButtonComponent {
         });
     }
 
+    /**
+     * @inheritdoc
+     */
+    ngOnDestroy(): void {
+        this.slotPromise?.cancel();
+    }
+
 }
diff --git a/src/core/features/course/format/singleactivity/components/core-course-format-single-activity.html b/src/core/features/course/format/singleactivity/components/core-course-format-single-activity.html
index 68eedcebf..aa42eeadb 100644
--- a/src/core/features/course/format/singleactivity/components/core-course-format-single-activity.html
+++ b/src/core/features/course/format/singleactivity/components/core-course-format-single-activity.html
@@ -1,4 +1,4 @@
 <core-dynamic-component [component]="componentClass" [data]="data"></core-dynamic-component>
 
-<core-block-side-blocks-button *ngIf="course && hasBlocks" [courseId]="course.id">
+<core-block-side-blocks-button slot="fixed" *ngIf="course && hasBlocks" [courseId]="course.id">
 </core-block-side-blocks-button>
diff --git a/src/core/features/courses/pages/dashboard/dashboard.html b/src/core/features/courses/pages/dashboard/dashboard.html
index 1e9771413..38dc1f17e 100644
--- a/src/core/features/courses/pages/dashboard/dashboard.html
+++ b/src/core/features/courses/pages/dashboard/dashboard.html
@@ -15,7 +15,7 @@
             </ng-container>
         </ion-list>
 
-        <core-block-side-blocks-button *ngIf="hasSideBlocks"></core-block-side-blocks-button>
+        <core-block-side-blocks-button slot="fixed" *ngIf="hasSideBlocks"></core-block-side-blocks-button>
 
         <core-empty-box *ngIf="blocks.length == 0" icon="fas-cubes" [message]="'core.course.nocontentavailable' | translate">
         </core-empty-box>
diff --git a/src/core/features/sitehome/pages/index/index.html b/src/core/features/sitehome/pages/index/index.html
index 97f7ba85a..f7c3d0856 100644
--- a/src/core/features/sitehome/pages/index/index.html
+++ b/src/core/features/sitehome/pages/index/index.html
@@ -45,7 +45,7 @@
                 </ng-container>
             </ng-container>
         </ion-list>
-        <core-block-side-blocks-button *ngIf="hasBlocks" [courseId]="siteHomeId">
+        <core-block-side-blocks-button slot="fixed" *ngIf="hasBlocks" [courseId]="siteHomeId">
         </core-block-side-blocks-button>
 
         <core-empty-box *ngIf="!hasContent" icon="fas-box-open" [message]="'core.course.nocontentavailable' | translate">
diff --git a/src/core/singletons/dom.ts b/src/core/singletons/dom.ts
index 7bb8be177..fdd0dd9d0 100644
--- a/src/core/singletons/dom.ts
+++ b/src/core/singletons/dom.ts
@@ -205,6 +205,38 @@ export class CoreDom {
         return CoreDom.scrollToElement(container, '.core-input-error');
     }
 
+    /**
+     * Move element to content so it can be slotted.
+     *
+     * @param element HTML Element.
+     * @param slot Slot name.
+     * @return Promise resolved when done.
+     */
+    static slotOnContent(element: HTMLElement, slot = 'fixed'): CoreCancellablePromise<void> {
+        element.setAttribute('slot', slot);
+        if (element.parentElement?.nodeName === 'ION-CONTENT') {
+            return CoreCancellablePromise.resolve();
+        }
+
+        const domPromise = CoreDom.waitToBeInDOM(element);
+
+        return new CoreCancellablePromise<void>(
+            async (resolve) => {
+                await domPromise;
+
+                // Move element to the nearest ion-content if it's not the parent
+                if (element.parentElement?.nodeName !== 'ION-CONTENT') {
+                    element.closest('ion-content')?.appendChild(element);
+                }
+
+                resolve();
+            },
+            () => {
+                domPromise.cancel();
+            },
+        );
+    }
+
     /**
      * Wait an element to be added to the root DOM.
      *