diff --git a/configs/linux/mozconfig b/configs/linux/mozconfig
index e4eacfdeb..04eac05b4 100644
--- a/configs/linux/mozconfig
+++ b/configs/linux/mozconfig
@@ -61,7 +61,7 @@ ac_add_options --enable-alsa
 ac_add_options --enable-pulseaudio
 
 if test "$ZEN_RELEASE"; then
-    #ac_add_options --enable-clang-plugin
+    ac_add_options --enable-clang-plugin
 
     # Disable DMD and ELF hacks, enable linker lld
     ac_add_options --disable-dmd
diff --git a/src/browser/base/content/ZenUIManager.mjs b/src/browser/base/content/ZenUIManager.mjs
index cb61eee03..594d4778f 100644
--- a/src/browser/base/content/ZenUIManager.mjs
+++ b/src/browser/base/content/ZenUIManager.mjs
@@ -117,6 +117,8 @@ var gZenUIManager = {
 
 var gZenVerticalTabsManager = {
   init() {
+    this._multiWindowFeature = new ZenMultiWindowFeature();
+
     ChromeUtils.defineLazyGetter(this, 'isWindowsStyledButtons', () => {
       return !(window.AppConstants.platform === 'macosx' || window.matchMedia('(-moz-gtk-csd-reversed-placement)').matches
         || Services.prefs.getBoolPref('zen.view.experimental-force-window-controls-left'));
@@ -138,7 +140,7 @@ var gZenVerticalTabsManager = {
     this.initRightSideOrderContextMenu();
 
     window.addEventListener('customizationstarting', this._preCustomize.bind(this));
-    window.addEventListener('aftercustomization', updateEvent);
+    window.addEventListener('aftercustomization', this._postCustomize.bind(this));
 
     window.addEventListener('DOMContentLoaded', updateEvent, { once: true });
 
@@ -209,12 +211,22 @@ var gZenVerticalTabsManager = {
     return this.__actualWindowButtons;
   },
 
-  _preCustomize() {
-    this._updateEvent({ forceMultipleToolbar: true });
+  async _preCustomize() {
+    await this._multiWindowFeature.foreachWindowAsActive(async (browser) => {
+      browser.gZenVerticalTabsManager._updateEvent({ forceMultipleToolbar: true, dontRebuildAreas: true });
+    });
+    this.rebuildAreas();
     this.navigatorToolbox.setAttribute('zen-sidebar-expanded', 'true');
     document.documentElement.setAttribute('zen-sidebar-expanded', 'true'); // force expanded sidebar
   },
 
+  _postCustomize() {
+    // No need to use `await` here, because the customization is already done
+    this._multiWindowFeature.foreachWindowAsActive(async (browser) => {
+      browser.gZenVerticalTabsManager._updateEvent({ dontRebuildAreas: true });
+    });
+  },
+
   initializePreferences(updateEvent) {
     XPCOMUtils.defineLazyPreferenceGetter(
       this,
@@ -261,7 +273,7 @@ var gZenVerticalTabsManager = {
     );
   },
 
-  _updateEvent({ forceMultipleToolbar = false } = {}) {
+  _updateEvent({ forceMultipleToolbar = false, dontRebuildAreas = false } = {}) {
     if (this._isUpdating) {
       return;
     }
@@ -314,16 +326,8 @@ var gZenVerticalTabsManager = {
         !isCompactMode
       ) {
         this.navigatorToolbox.prepend(topButtons);
-      //  browser.prepend(this.navigatorToolbox);
-      } else {
-      //  customizationTarget.prepend(topButtons);
-      //  tabboxWrapper.prepend(this.navigatorToolbox);
       }
 
-      //if (!isVerticalTabs) {
-      //  document.getElementById("urlbar-container").after(document.getElementById('navigator-toolbox'));
-      //}
-
       let windowButtons = this.actualWindowButtons;
       let doNotChangeWindowButtons = !isCompactMode && isRightSide && this.isWindowsStyledButtons;
       const navBar = document.getElementById('nav-bar');
@@ -365,7 +369,9 @@ var gZenVerticalTabsManager = {
         document.documentElement.removeAttribute("zen-single-toolbar");
         navBar.appendChild(document.getElementById('PanelUI-button'));
         this._toolbarOriginalParent.prepend(navBar);
-        this.rebuildAreas();
+        if (!dontRebuildAreas) {
+          this.rebuildAreas();
+        }
       }
 
       if (isCompactMode) {
diff --git a/src/browser/base/content/zen-styles/zen-workspaces.css b/src/browser/base/content/zen-styles/zen-workspaces.css
index 249a4c323..48340aea2 100644
--- a/src/browser/base/content/zen-styles/zen-workspaces.css
+++ b/src/browser/base/content/zen-styles/zen-workspaces.css
@@ -437,7 +437,7 @@
   }
 }
 
-@media (-moz-bool-pref: 'zen.workspaces.show-workspace-indicator') or (not (-moz-bool-pref: 'zen.workspaces.enabled')) {
+@media (not (-moz-bool-pref: 'zen.workspaces.show-workspace-indicator')) or (not (-moz-bool-pref: 'zen.workspaces.enabled')) {
   #zen-current-workspace-indicator {
     display: none !important;
   }
diff --git a/src/browser/base/zen-components/ZenCommonUtils.mjs b/src/browser/base/zen-components/ZenCommonUtils.mjs
index 4c5c6d37e..4b151ee65 100644
--- a/src/browser/base/zen-components/ZenCommonUtils.mjs
+++ b/src/browser/base/zen-components/ZenCommonUtils.mjs
@@ -22,12 +22,16 @@ class ZenMultiWindowFeature {
     return Services.wm.getMostRecentWindow('navigator:browser');
   }
 
-  isActiveWindow() {
+  static get isActiveWindow() {
     return ZenMultiWindowFeature.currentBrowser === window;
   }
 
+  windowIsActive(browser) {
+    return browser === ZenMultiWindowFeature.currentBrowser;
+  }
+
   async foreachWindowAsActive(callback) {
-    if (!this.isActiveWindow()) {
+    if (!ZenMultiWindowFeature.isActiveWindow) {
       return;
     }
     for (const browser of ZenMultiWindowFeature.browsers) {