[已解决]userchrome.js怎样用快捷键调用？

(function(){
    var item = document.createElement('menuitem');
    item.setAttribute('label', '\u5173\u95ED\u53F3\u4FA7\u7684\u6807\u7B7E');
    item.setAttribute('accesskey', '2');
    item.addEventListener('command', function(){
        var tabs = gBrowser.mTabContainer.childNodes;
        for(var i = tabs.length - 1; tabs != document.popupNode; i--){
            gBrowser.removeTab(tabs);
        }
    }, false);
    setTimeout(function(){
        gBrowser.mStrip.childNodes[1].appendChild(item);
    }, 0);
})();

var tabs = gBrowser.mTabContainer.childNodes;
                for(var i = tabs.length - 1; tabs != document.popupNode; i--){
                    gBrowser.removeTab(tabs);
                }
        }, false);