add:  window.XULBrowserWindow.destroy(); window.XULBrowserWindow = null; 
context: function Shutdown(){  var browser = getBrowser();  browser.boxObject.removeProperty("listenerkungfu");  try {    var interfaceRequestor = browser.docShell.QueryInterface(Components.interfaces.nsIInterfaceRequestor);    var webProgress = interfaceRequestor.getInterface(Components.interfaces.nsIWebProgress);    webProgress.removeProgressListener(appCore);  } catch (ex) {  }  try {    // If bookmarks are dirty, flush 'em to disk    var bmks = Components.classes["@mozilla.org/browser/bookmarks-service;1"]                         .getService(Components.interfaces.nsIRDFRemoteDataSource);    bmks.Flush();  } catch (ex) {  }  try {    // give history a chance at flushing to disk also    var history = Components.classes["@mozilla.org/browser/global-history;1"]                            .getService(Components.interfaces.nsIRDFRemoteDataSource);    history.Flush();  } catch (ex) {  }  // unregister us as a pref listener  pref.removeObserver(window.buttonPrefListener.domain,                      window.buttonPrefListener);  // Close the app core.  if (appCore)    appCore.close();}
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/5ad5ad4564a3e8ded6376bb59916e22c4051d1d5/navigator.js/clean/xpfe/browser/resources/content/navigator.js