add: pref.removeObserver("mail.pane_config.dynamic", MailPaneConfigObserver, false);  
context: function OnUnloadMessenger(){  accountManager.removeIncomingServerListener(gThreePaneIncomingServerListener);  RemoveToolBarPrefListener();  // FIX ME - later we will be able to use onload from the overlay  OnUnloadMsgHeaderPane();  OnMailWindowUnload();}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/4df13a26fdf3adc16683aa4e7543afeb086f163a/msgMail3PaneWindow.js/buggy/mailnews/base/resources/content/msgMail3PaneWindow.js