add: osvr.removeObserver(this, "prefservice:after-app-defaults"); 
context:   _dispose: function()   {    // observer removal     const osvr = Cc['@mozilla.org/observer-service;1'].                 getService(Ci.nsIObserverService);    osvr.removeObserver(this, "profile-before-change");    osvr.removeObserver(this, "profile-change-teardown");    osvr.removeObserver(this, "xpcom-shutdown");    osvr.removeObserver(this, "final-ui-startup");    osvr.removeObserver(this, "browser:purge-session-history");    osvr.removeObserver(this, "quit-application-requested");    osvr.removeObserver(this, "quit-application-granted");  },
meta: 8395	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/8395/cde460cf9572e897ca57976e5c5587acbbefe26c/nsBrowserGlue.js/clean/browser/components/nsBrowserGlue.js