add: window.addEventListener("unload", this, false); 
context: function calendarPrefObserver( CalendarPreferences ){   this.CalendarPreferences = CalendarPreferences;   try {     var pbi = rootPrefNode.QueryInterface(Components.interfaces.nsIPrefBranchInternal);     pbi.addObserver("calendar", this, false);  } catch(ex) {    dump("Calendar: Failed to observe prefs: " + ex + "\n");  }}
meta: 8395	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/8395/b8c2eec906363c0e938d2adfbbd1740ecebb0f00/rootCalendarPref.js/buggy/calendar/resources/content/pref/rootCalendarPref.js