diff --git a/Build/Sources/TypeScript/backend/viewport/resizable-navigation.ts b/Build/Sources/TypeScript/backend/viewport/resizable-navigation.ts
index 94ca1412c27bdaa1d7feb3f68a31f095924883f0..5d20032b7d851f86e6bc75566ffed04a7c8cf63e 100644
--- a/Build/Sources/TypeScript/backend/viewport/resizable-navigation.ts
+++ b/Build/Sources/TypeScript/backend/viewport/resizable-navigation.ts
@@ -74,10 +74,10 @@ export class ResizableNavigation extends LitElement {
   protected render(): TemplateResult {
     return html`
       <div class="scaffold-content-navigation-switcher">
-        <button @mouseup="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-open" role="button" title="${lll('viewport_navigation_show')}">
+        <button @click="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-open" role="button" title="${lll('viewport_navigation_show')}">
           <typo3-backend-icon identifier="actions-chevron-right" size="small"></typo3-backend-icon>
         </button>
-        <button @mouseup="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-close" role="button" title="${lll('viewport_navigation_hide')}">
+        <button @click="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-close" role="button" title="${lll('viewport_navigation_hide')}">
           <typo3-backend-icon identifier="actions-chevron-left" size="small"></typo3-backend-icon>
         </button>
       </div>
@@ -85,12 +85,14 @@ export class ResizableNavigation extends LitElement {
     `;
   }
 
-  private readonly toggleNavigation = (event: MouseEvent | TouchEvent) => {
-    if (event instanceof MouseEvent && event.button === 2) {
-      return;
-    }
+  private readonly toggleNavigation = (event: MouseEvent | TouchEvent | KeyboardEvent) => {
     event.stopPropagation();
     this.parentContainer.classList.toggle('scaffold-content-navigation-expanded');
+
+    if (event.currentTarget instanceof HTMLElement) {
+      const sibling = (event.currentTarget.nextElementSibling ?? event.currentTarget.previousElementSibling) as HTMLElement;
+      sibling.focus();
+    }
   };
 
   private readonly fallbackNavigationSizeIfNeeded = (event: UIEvent) => {
diff --git a/typo3/sysext/backend/Resources/Public/JavaScript/viewport/resizable-navigation.js b/typo3/sysext/backend/Resources/Public/JavaScript/viewport/resizable-navigation.js
index a314950439c515b2cee7fc9241e0f764b7540ce3..52e3c2441ff3de99f218d9900525ee4c17c9b622 100644
--- a/typo3/sysext/backend/Resources/Public/JavaScript/viewport/resizable-navigation.js
+++ b/typo3/sysext/backend/Resources/Public/JavaScript/viewport/resizable-navigation.js
@@ -10,12 +10,12 @@
  *
  * The TYPO3 project - inspiring people to share!
  */
-var __decorate=function(t,e,i,n){var o,a=arguments.length,s=a<3?e:null===n?n=Object.getOwnPropertyDescriptor(e,i):n;if("object"==typeof Reflect&&"function"==typeof Reflect.decorate)s=Reflect.decorate(t,e,i,n);else for(var r=t.length-1;r>=0;r--)(o=t[r])&&(s=(a<3?o(s):a>3?o(e,i,s):o(e,i))||s);return a>3&&s&&Object.defineProperty(e,i,s),s};import{html,LitElement}from"lit";import{customElement,property,state}from"lit/decorators.js";import{lll}from"@typo3/core/lit-helper.js";import Persistent from"@typo3/backend/storage/persistent.js";import"@typo3/backend/element/icon-element.js";const selectorConverter={fromAttribute:t=>document.querySelector(t)};var ReadingModeDirection;!function(t){t.ltr="ltr",t.rtl="rtl"}(ReadingModeDirection||(ReadingModeDirection={}));class ReadingMode{static get(){return"rtl"===document.querySelector("html").dir?ReadingModeDirection.rtl:ReadingModeDirection.ltr}}let ResizableNavigation=class extends LitElement{constructor(){super(...arguments),this.minimumWidth=250,this.resizing=!1,this.toggleNavigation=t=>{t instanceof MouseEvent&&2===t.button||(t.stopPropagation(),this.parentContainer.classList.toggle("scaffold-content-navigation-expanded"))},this.fallbackNavigationSizeIfNeeded=t=>{const e=t.currentTarget;0!==this.getNavigationWidth()&&e.outerWidth<this.getNavigationWidth()+this.getNavigationPosition().left+this.minimumWidth&&this.autoNavigationWidth()},this.handleMouseMove=t=>{this.resizeNavigation(t.clientX)},this.handleTouchMove=t=>{this.resizeNavigation(t.changedTouches[0].clientX)},this.resizeNavigation=t=>{let e=0;e=ReadingMode.get()===ReadingModeDirection.ltr?Math.round(t)-Math.round(this.getNavigationPosition().left):Math.round(this.getNavigationPosition().right)-Math.round(t),this.setNavigationWidth(e)},this.startResizeNavigation=t=>{t instanceof MouseEvent&&2===t.button||(t.stopPropagation(),this.resizing=!0,document.addEventListener("mousemove",this.handleMouseMove,!1),document.addEventListener("mouseup",this.stopResizeNavigation,!1),document.addEventListener("touchmove",this.handleTouchMove,!1),document.addEventListener("touchend",this.stopResizeNavigation,!1))},this.stopResizeNavigation=()=>{this.resizing=!1,document.removeEventListener("mousemove",this.handleMouseMove,!1),document.removeEventListener("mouseup",this.stopResizeNavigation,!1),document.removeEventListener("touchmove",this.handleTouchMove,!1),document.removeEventListener("touchend",this.stopResizeNavigation,!1),Persistent.set(this.persistenceIdentifier,this.getNavigationWidth()),document.dispatchEvent(new CustomEvent("typo3:navigation:resized"))}}connectedCallback(){super.connectedCallback();const t=this.initialWidth||parseInt(Persistent.get(this.persistenceIdentifier),10);this.setNavigationWidth(t),window.addEventListener("resize",this.fallbackNavigationSizeIfNeeded,{passive:!0})}disconnectedCallback(){super.disconnectedCallback(),window.removeEventListener("resize",this.fallbackNavigationSizeIfNeeded)}createRenderRoot(){return this}async firstUpdated(){await new Promise((t=>setTimeout(t,0))),this.querySelector(".scaffold-content-navigation-switcher-btn").addEventListener("touchstart",this.toggleNavigation,{passive:!0}),this.querySelector(".scaffold-content-navigation-drag").addEventListener("touchstart",this.startResizeNavigation,{passive:!0})}render(){return html`
+var __decorate=function(t,e,i,n){var o,a=arguments.length,s=a<3?e:null===n?n=Object.getOwnPropertyDescriptor(e,i):n;if("object"==typeof Reflect&&"function"==typeof Reflect.decorate)s=Reflect.decorate(t,e,i,n);else for(var r=t.length-1;r>=0;r--)(o=t[r])&&(s=(a<3?o(s):a>3?o(e,i,s):o(e,i))||s);return a>3&&s&&Object.defineProperty(e,i,s),s};import{html,LitElement}from"lit";import{customElement,property,state}from"lit/decorators.js";import{lll}from"@typo3/core/lit-helper.js";import Persistent from"@typo3/backend/storage/persistent.js";import"@typo3/backend/element/icon-element.js";const selectorConverter={fromAttribute:t=>document.querySelector(t)};var ReadingModeDirection;!function(t){t.ltr="ltr",t.rtl="rtl"}(ReadingModeDirection||(ReadingModeDirection={}));class ReadingMode{static get(){return"rtl"===document.querySelector("html").dir?ReadingModeDirection.rtl:ReadingModeDirection.ltr}}let ResizableNavigation=class extends LitElement{constructor(){super(...arguments),this.minimumWidth=250,this.resizing=!1,this.toggleNavigation=t=>{if(t.stopPropagation(),this.parentContainer.classList.toggle("scaffold-content-navigation-expanded"),t.currentTarget instanceof HTMLElement){(t.currentTarget.nextElementSibling??t.currentTarget.previousElementSibling).focus()}},this.fallbackNavigationSizeIfNeeded=t=>{const e=t.currentTarget;0!==this.getNavigationWidth()&&e.outerWidth<this.getNavigationWidth()+this.getNavigationPosition().left+this.minimumWidth&&this.autoNavigationWidth()},this.handleMouseMove=t=>{this.resizeNavigation(t.clientX)},this.handleTouchMove=t=>{this.resizeNavigation(t.changedTouches[0].clientX)},this.resizeNavigation=t=>{let e=0;e=ReadingMode.get()===ReadingModeDirection.ltr?Math.round(t)-Math.round(this.getNavigationPosition().left):Math.round(this.getNavigationPosition().right)-Math.round(t),this.setNavigationWidth(e)},this.startResizeNavigation=t=>{t instanceof MouseEvent&&2===t.button||(t.stopPropagation(),this.resizing=!0,document.addEventListener("mousemove",this.handleMouseMove,!1),document.addEventListener("mouseup",this.stopResizeNavigation,!1),document.addEventListener("touchmove",this.handleTouchMove,!1),document.addEventListener("touchend",this.stopResizeNavigation,!1))},this.stopResizeNavigation=()=>{this.resizing=!1,document.removeEventListener("mousemove",this.handleMouseMove,!1),document.removeEventListener("mouseup",this.stopResizeNavigation,!1),document.removeEventListener("touchmove",this.handleTouchMove,!1),document.removeEventListener("touchend",this.stopResizeNavigation,!1),Persistent.set(this.persistenceIdentifier,this.getNavigationWidth()),document.dispatchEvent(new CustomEvent("typo3:navigation:resized"))}}connectedCallback(){super.connectedCallback();const t=this.initialWidth||parseInt(Persistent.get(this.persistenceIdentifier),10);this.setNavigationWidth(t),window.addEventListener("resize",this.fallbackNavigationSizeIfNeeded,{passive:!0})}disconnectedCallback(){super.disconnectedCallback(),window.removeEventListener("resize",this.fallbackNavigationSizeIfNeeded)}createRenderRoot(){return this}async firstUpdated(){await new Promise((t=>setTimeout(t,0))),this.querySelector(".scaffold-content-navigation-switcher-btn").addEventListener("touchstart",this.toggleNavigation,{passive:!0}),this.querySelector(".scaffold-content-navigation-drag").addEventListener("touchstart",this.startResizeNavigation,{passive:!0})}render(){return html`
       <div class="scaffold-content-navigation-switcher">
-        <button @mouseup="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-open" role="button" title="${lll("viewport_navigation_show")}">
+        <button @click="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-open" role="button" title="${lll("viewport_navigation_show")}">
           <typo3-backend-icon identifier="actions-chevron-right" size="small"></typo3-backend-icon>
         </button>
-        <button @mouseup="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-close" role="button" title="${lll("viewport_navigation_hide")}">
+        <button @click="${this.toggleNavigation}" class="btn btn-default btn-borderless scaffold-content-navigation-switcher-btn scaffold-content-navigation-switcher-close" role="button" title="${lll("viewport_navigation_hide")}">
           <typo3-backend-icon identifier="actions-chevron-left" size="small"></typo3-backend-icon>
         </button>
       </div>