add: const XULAPPINFO_CONTRACTID = "@mozilla.org/xre/app-info;1"; const nsIXULAppInfo = Components.interfaces.nsIXULAppInfo; 
context: function isThunderbird(){    var cls = Components.classes[XULAPPINFO_CONTRACTID];    if (!cls)        return false;    var appinfo;    try    {        // This throws when it gets upset.        appinfo = cls.getService(nsIXULAppInfo);    }    catch(ex) {}    if (!appinfo)        return false;    return (appinfo.ID == "{3550f703-e582-4d05-9a08-453d09bdfdc6}");}
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/c6f8333e796a4f66f75cf626f98516c8629a35b3/venkman-overlay.js/buggy/extensions/venkman/resources/content/venkman-overlay.js