diff -r 000000000000 -r 6474c204b198 toolkit/themes/osx/global/progressmeter.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/themes/osx/global/progressmeter.css	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,22 @@
+/* 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");
+
+progressmeter {
+  -moz-appearance: progressbar;
+  margin: 2px 4px;
+  min-width: 128px;
+  height: 12px;
+}
+
+.progress-remainder[flex="100"], .progress-remainder[flex="0"] {
+  background-image: none !important;
+  -moz-appearance: none;
+}
+
+.progressmeter-statusbar {
+  margin: 0;
+  border-width: 1px;
+}