--- a/toolkit/themes/osx/global/toolbarbutton.css
+++ b/toolkit/themes/osx/global/toolbarbutton.css
@@ -2,20 +2,18 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
 
 toolbarbutton {
   -moz-box-align: center;
   -moz-box-pack: center;
-  margin: 0px 2px 0px 2px;
-  padding: 3px 1px 3px 1px;
-  border-right: 1px solid transparent;
-  border-left: 1px solid transparent;
+  margin: 0 2px;
+  padding: 3px 2px;
   background-color: transparent;
   text-shadow: 0 1px 0 rgba(255, 255, 255, 0.4);
 }
 
 toolbarbutton[open="true"],
 toolbarbutton:not([disabled="true"]):active:hover {
   text-shadow: none;
 }