diff --git a/configs/linux/mozconfig b/configs/linux/mozconfig
index 7f7fea705..8f7117c06 100644
--- a/configs/linux/mozconfig
+++ b/configs/linux/mozconfig
@@ -33,6 +33,10 @@ elif test "$SURFER_COMPAT" = "aarch64"; then
 
     ac_add_options --enable-optimize="-O3"
 
+    # Enable Profile Guided Optimization
+    export MOZ_PGO=1
+    ac_add_options MOZ_PGO=1
+
     if ! test "$ZEN_DISABLE_LTO"; then
       export MOZ_LTO=cross,thin
       ac_add_options --enable-lto=cross,thin
diff --git a/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs-topbar.inc.css b/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs-topbar.inc.css
index b5db1e5dc..83b9f39d2 100644
--- a/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs-topbar.inc.css
+++ b/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs-topbar.inc.css
@@ -31,10 +31,3 @@ height: var(--zen-toolbar-height);
     }
   }
 }
-
-:root[inDOMFullscreen='true'] & {
-  max-height: 0 !important;
-  min-height: unset !important;
-  opacity: 0 !important;
-  pointer-events: none !important;
-}
diff --git a/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs.css b/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs.css
index 74d92a0e4..e5c1361fe 100644
--- a/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs.css
+++ b/src/browser/base/content/zen-styles/zen-tabs/vertical-tabs.css
@@ -166,6 +166,13 @@
     &[should-hide='true'] {
 %include vertical-tabs-topbar.inc.css
     }
+
+    :root[inDOMFullscreen='true'] & {
+      max-height: 0 !important;
+      min-height: unset !important;
+      opacity: 0 !important;
+      pointer-events: none !important;
+    }
   }
 }