gecko/browser/themes/pinstripe/feeds/subscribe-ui.css

/* 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/. */

.alwaysUse {
  padding: 3px;
}

.chooseApplicationMenuItem {
  list-style-image: url("chrome://browser/skin/preferences/application.png");
}