Remove opacity changes from titlebar - fixes #331

Bug 1870803 introduced a transition to window activeness visuals. But
the lowered opacity breaks the z-index hackery we use to let
window-controls show through nav-bar.

This patch basically undoes the changes from bug 1870803

chrome/tabs_below_content.css

@@ -19,7 +19,11 @@ linux_gtk_window_control_patch.css
   z-index: 3;
   visibility: visible !important;
 }
-
+#titlebar{
+  will-change: unset !important;
+  transition: none !important;
+  opacity: 1 !important;
+}
 @media (-moz-bool-pref: "userchrome.force-window-controls-on-left.enabled"),
        (-moz-gtk-csd-reversed-placement),
        (-moz-platform: macos){