add:  /* Hackaround, bug 314230. XBL likes focusing a tab before onload has fired. * That means the tab we're trying to select here will be the hidden one, * which doesn't have a viewKey. We catch that case. */ if (!tabs.selectedItem.hasAttribute("viewKey")) return;  
context: function onTabSelect(e){    var tabs = e.target;    var key = tabs.selectedItem.getAttribute("viewKey");    var view = client.viewsArray[key];    dispatch("set-current-view", {view:view.source});}
meta: 1567	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1567/76b4c39e8ff8feac20857774b6bf014478021d52/handlers.js/buggy/xul/content/handlers.js