--- /dev/null
+/* 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");
+
+panel[type="arrow"][side="top"],
+panel[type="arrow"][side="bottom"] {
+ margin-left: 0;
+ margin-right: 0;
+}