diff -r 000000000000 -r 6474c204b198 toolkit/themes/osx/global/filepicker.css
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolkit/themes/osx/global/filepicker.css	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,40 @@
+/* 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/. */
+
+@import url("chrome://global/skin/");
+
+@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
+
+/* ::::: column widths ::::: */
+
+#FilenameColumn,
+#ContentLengthColumn,
+#LastModifiedDateColumn {
+  width: 100px;
+}
+
+/* ::::: file/directory items ::::: */
+
+treechildren::-moz-tree-image(treecolAutoCompleteValue, directory),
+treechildren::-moz-tree-image(FilenameColumn, directory) {
+  margin-right: 2px;
+  list-style-image: url("chrome://global/skin/filepicker/dir-closed.gif");
+}
+
+treechildren::-moz-tree-image(treecolAutoCompleteValue, file),
+treechildren::-moz-tree-image(FilenameColumn, file) {
+  list-style-image: url("chrome://global/skin/filepicker/blank.gif");
+}
+
+/* ::::: button items ::::: */
+
+.up-button {
+  list-style-image: url("chrome://global/skin/filepicker/folder-up.gif");
+  max-width: 36px;
+}
+
+.home-button {
+  list-style-image: url("chrome://global/skin/filepicker/folder-home.gif");
+  max-width: 36px;
+}