dieses Script funktioniert nicht mehr ?

(function() {
if (location != 'chrome://browser/content/browser.xul')
return;
var menuButton = document.getElementById('PanelUI-menu-button');


if (!CustomizableUI.getPlacementOfWidget('ucjs_PanelUI-button')) {
try {
CustomizableUI.createWidget({
id: 'ucjs_PanelUI-button',
type: 'custom',
defaultArea: CustomizableUI.AREA_NAVBAR,
onBuild: function(aDocument) {
var toolbaritem = aDocument.createElementNS('http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul', 'toolbaritem');
toolbaritem.id = 'ucjs_PanelUI-button';
toolbaritem.className = 'chromeclass-toolbar-additional';

toolbaritem.setAttribute('label', 'Firefox Anpassen');
return toolbaritem;
}
});
if (!CustomizableUI.getPlacementOfWidget('ucjs_PanelUI-button')) {
menuButton.style.display = 'none';
return;
};
} catch(e) {
menuButton.style.display = 'none';
return;
};
};




setTimeout(function() {
document.getElementById('ucjs_PanelUI-button').appendChild(menuButton);
menuButton.setAttribute('consumeanchor', 'ucjs_PanelUI-button');
menuButton.setAttribute('label', 'Firefox Anpassen');
menuButton.setAttribute('tooltiptext', 'Firefox Anpassen + Panel');
}, 0);




}());