rem: document.getElementById('web-panels-browser').webProgress.removeProgressListener(panelProgressListener); 
add: var panelBrowser = document.getElementById('web-panels-browser'); panelBrowser.webProgress.removeProgressListener(panelProgressListener); 
context: function unload(){  document.getElementById('web-panels-browser').webProgress.removeProgressListener(panelProgressListener);}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/14f8c8dd6f859c05aed7dd144962204d48a127a5/web-panels.js/buggy/browser/base/content/web-panels.js