--- a/browser/base/content/browser-allTabsMenu.js
+++ b/browser/base/content/browser-allTabsMenu.js
@@ -13,21 +13,25 @@ var gTabsPanel = {
     allTabsButton: "alltabs-button",
     allTabsView: "allTabsMenu-allTabsView",
     allTabsViewTabs: "allTabsMenu-allTabsViewTabs",
     containerTabsView: "allTabsMenu-containerTabsView",
     hiddenTabsButton: "allTabsMenu-hiddenTabsButton",
     hiddenTabsView: "allTabsMenu-hiddenTabsView",
   },
   _initialized: false,
+  _initializedElements: false,
 
   initElements() {
+    if (this._initializedElements) return;
+
     for (let [name, id] of Object.entries(this.kElements)) {
       this[name] = document.getElementById(id);
     }
+    this._initializedElements = true;
   },
 
   init() {
     if (this._initialized) return;
 
     this.initElements();
 
     let hiddenTabsMenuButton = this.allTabsView.querySelector(".hidden-tabs-button");
@@ -119,26 +123,36 @@ var gTabsPanel = {
     this.hiddenTabsPopup = new TabsPanel({
       view: this.hiddenTabsView,
       filterFn: (tab) => tab.hidden,
     });
 
     this._initialized = true;
   },
 
+  get canOpen() {
+    this.initElements();
+    return isElementVisible(this.allTabsButton);
+  },
+
   showAllTabsPanel() {
     this.init();
-    PanelUI.showSubView(this.kElements.allTabsView, this.allTabsButton);
+    if (this.canOpen) {
+      PanelUI.showSubView(this.kElements.allTabsView, this.allTabsButton);
+    }
   },
 
   hideAllTabsPanel() {
     this.init();
     PanelMultiView.hidePopup(this.allTabsView.closest("panel"));
   },
 
   showHiddenTabsPanel() {
     this.init();
+    if (!this.canOpen) {
+      return;
+    }
     this.allTabsView.addEventListener("ViewShown", (e) => {
       PanelUI.showSubView(this.kElements.hiddenTabsView, this.hiddenTabsButton);
     }, {once: true});
     this.showAllTabsPanel();
   },
 };

--- a/browser/base/content/browser-ctrlTab.js
+++ b/browser/base/content/browser-ctrlTab.js
@@ -289,17 +289,17 @@ var ctrlTab = {
 
   updatePreviews: function ctrlTab_updatePreviews() {
     for (let i = 0; i < this.previews.length; i++)
       this.updatePreview(this.previews[i], this.tabList[i]);
 
     var showAllLabel = gNavigatorBundle.getString("ctrlTab.listAllTabs.label");
     this.showAllButton._label.setAttribute("value",
       PluralForm.get(this.tabCount, showAllLabel).replace("#1", this.tabCount));
-    this.showAllButton.hidden = !allTabs.canOpen;
+    this.showAllButton.hidden = !gTabsPanel.canOpen;
   },
 
   updatePreview: function ctrlTab_updatePreview(aPreview, aTab) {
     if (aPreview == this.showAllButton)
       return;
 
     aPreview._tab = aTab;
 
@@ -565,17 +565,17 @@ var ctrlTab = {
         this.onKeyPress(event);
         break;
       case "keyup":
         if (event.keyCode == event.DOM_VK_CONTROL)
           this.pick();
         break;
       case "popupshowing":
         if (event.target.id == "menu_viewPopup")
-          document.getElementById("menu_showAllTabs").hidden = !allTabs.canOpen;
+          document.getElementById("menu_showAllTabs").hidden = !gTabsPanel.canOpen;
         break;
     }
   },
 
   filterForThumbnailExpiration(aCallback) {
     // Save a few more thumbnails than we actually display, so that when tabs
     // are closed, the previews we add instead still get thumbnails.
     const extraThumbnails = 3;
@@ -623,32 +623,8 @@ var ctrlTab = {
     // Show All Tabs.
     var key_showAllTabs = document.getElementById("key_showAllTabs");
     if (enable)
       key_showAllTabs.removeAttribute("disabled");
     else
       key_showAllTabs.setAttribute("disabled", "true");
   }
 };
-
-
-/**
- * All Tabs menu
- */
-var allTabs = {
-  get toolbarButton() {
-    return document.getElementById("alltabs-button");
-  },
-
-  get canOpen() {
-    return isElementVisible(this.toolbarButton);
-  },
-
-  open: function allTabs_open() {
-    if (this.canOpen) {
-      // Without setTimeout, the menupopup won't stay open when invoking
-      // "View > Show All Tabs" and the menu bar auto-hides.
-      setTimeout(() => {
-        this.toolbarButton.open = true;
-      }, 0);
-    }
-  }
-};

--- a/browser/base/content/browser-sets.inc
+++ b/browser/base/content/browser-sets.inc
@@ -76,17 +76,17 @@
     <command id="Browser:ReloadOrDuplicate" oncommand="BrowserReloadOrDuplicate(event)" disabled="true">
       <observes element="Browser:Reload" attribute="disabled"/>
     </command>
     <command id="Browser:ReloadSkipCache" oncommand="BrowserReloadSkipCache()" disabled="true">
       <observes element="Browser:Reload" attribute="disabled"/>
     </command>
     <command id="Browser:NextTab" oncommand="gBrowser.tabContainer.advanceSelectedTab(1, true);"/>
     <command id="Browser:PrevTab" oncommand="gBrowser.tabContainer.advanceSelectedTab(-1, true);"/>
-    <command id="Browser:ShowAllTabs" oncommand="allTabs.open();"/>
+    <command id="Browser:ShowAllTabs" oncommand="gTabsPanel.showAllTabsPanel();"/>
     <command id="cmd_fullZoomReduce"  oncommand="FullZoom.reduce()"/>
     <command id="cmd_fullZoomEnlarge" oncommand="FullZoom.enlarge()"/>
     <command id="cmd_fullZoomReset"   oncommand="FullZoom.reset()"/>
     <command id="cmd_fullZoomToggle"  oncommand="ZoomManager.toggleZoom();"/>
     <command id="cmd_gestureRotateLeft" oncommand="gGestureSupport.rotate(event.sourceEvent)"/>
     <command id="cmd_gestureRotateRight" oncommand="gGestureSupport.rotate(event.sourceEvent)"/>
     <command id="cmd_gestureRotateEnd" oncommand="gGestureSupport.rotateEnd()"/>
     <command id="Browser:OpenLocation" oncommand="openLocation();"/>