diff -r 000000000000 -r 6474c204b198 toolkit/themes/osx/global/filefield.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/themes/osx/global/filefield.css	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,38 @@
+/*
+# -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+# 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/.
+*/
+
+.fileFieldIcon {
+  width: 16px;
+  height: 16px;
+}
+
+.fileFieldIcon[disabled="true"] {
+  opacity: 0.5;
+}
+
+filefield {
+  margin: 4px;
+  -moz-margin-start: 27px;
+  -moz-appearance: textfield;
+}
+
+.fileFieldContentBox {
+  margin: -3px;
+  background-color: rgba(230, 230, 230, 0.6);
+  color: -moz-DialogText;
+  padding-top: 2px;
+  padding-bottom: 2px;
+  -moz-padding-start: 5px;
+  -moz-padding-end: 3px;
+}
+
+.fileFieldLabel {
+  -moz-appearance: none;
+  background-color: transparent;
+  border: none;
+  margin: 0 4px;
+}