let { classes: Cc, utils: Cu, interfaces: Ci } = Components; let cs = Cc["@mozilla.org/cookiemanager;1"] .getService(Ci.nsICookieManager2); addMessageListener("getCookieCountAndClear", () => { let count = 0; for (let list = cs.enumerator; list.hasMoreElements(); list.getNext()) ++count; cs.removeAll(); sendAsyncMessage("getCookieCountAndClear:return", { count }); }); cs.removeAll();