Fix for 40444; don't allow buttons to steal focus willy-nilly, because this breaks toolbar buttons. What really needs to happen is that every kind of toolbar buttons needs user-focus: none style. r=hyatt, a=leaf

xpfe/global/resources/skin/xul.css

@@ -290,7 +290,7 @@ radiogroup
   }
 
 button, button.left {
-  user-focus: normal;
+  /* user-focus: normal; */
   behavior: url(resource:/chrome/xulBindings.xml#buttonleft);
 }