add: osvr.removeObserver(this, "profile-before-change"); 
context:   _dispose: function()   {    // observer removal     const osvr = Components.classes['@mozilla.org/observer-service;1']                           .getService(Components.interfaces.nsIObserverService);    osvr.removeObserver(this, "profile-change-teardown");    osvr.removeObserver(this, "xpcom-shutdown");    osvr.removeObserver(this, "final-ui-startup");    osvr.removeObserver(this, "browser:purge-session-history");  },
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/10234/afd0626a7dbe3f29de598317e51226fdd56cc7c3/nsBrowserGlue.js/clean/browser/components/nsBrowserGlue.js