rem: webProgress.removeProgressListener(GM_DocStartListener); 
add: Components.classes["@mozilla.org/docloaderservice;1"] .getService(Components.interfaces.nsIWebProgress) .removeProgressListener(GM_DocStartListener); 
context: window.addEventListener("unload", function() {  webProgress.removeProgressListener(GM_DocStartListener);}, false);
meta: 9744	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9744/bb15ba07d80451d03ef5be42d32c71c9f78959f0/browser.js/buggy/src/content/browser.js