Bug 1052466 - [10.10] Update titlebar/toolbar to use transparency on OS X Yosemite, r=mstange,f=gijs

browser/themes/osx/browser.css

@@ -102,6 +102,12 @@
   -moz-appearance: -moz-window-titlebar;
 }
 
+@media (-moz-mac-yosemite-theme) {
+  #main-window:not(:-moz-lwtheme) > #titlebar {
+    -moz-appearance: -moz-mac-vibrancy-light;
+  }
+}
+
 #main-window:not([tabsintitlebar]) > #titlebar {
   height: 22px; /* The native titlebar on OS X is 22px tall. */
 }