diff -r 000000000000 -r 6474c204b198 toolkit/themes/osx/global/groupbox.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/themes/osx/global/groupbox.css	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,30 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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");
+
+groupbox {
+  padding: 5px 1px 1px;
+  -moz-padding-start: 0;
+  margin: 6px;
+}
+
+.groupbox-body {
+  -moz-appearance: groupbox;
+  padding: 8px 8px 3px;
+  margin: 0;
+}
+
+caption {
+  -moz-padding-start: 4px;
+  padding-bottom: 1px;
+  font: caption;
+}
+
+/* !important is needed to override label in global.css */
+.caption-text {
+  margin-top: 0 !important;
+  margin-bottom: 0 !important;
+  -moz-margin-start: 1px !important;
+}