autohide_menubar.css: Increase the size of menubar triggering area

The window frame area (at least on Win10) is wider in Fx98 which
prevents menubar items from showing up. This patch simply increases the
size by few pixels.

chrome/autohide_menubar.css

@@ -5,7 +5,7 @@ See the above repository for updates as well as full license text. */
 /* Menubar will be shown when cursor touches top of the spacers on both side of tabs. Window controls will be in menubar, so they are automatically hidden */
 /* Make sure you have menubar enabled */
 
-:root{ --uc-menubar-spacer: 6px }
+:root{ --uc-menubar-spacer: 11px }
 :root[sizemode="maximized"]{ --uc-menubar-spacer: 1px }
 
 #nav-bar-customization-target,
@@ -38,5 +38,7 @@ See the above repository for updates as well as full license text. */
   z-index: 6
 }
 
+#main-menubar > menu{ padding-bottom: 4px }
+
 /* This exists only for compatibility reasons with some other styles */
 #navigator-toolbox{ --uc-hide-window-control-space: 0 }