rem: return window.toolbar.visible; 
add: return !window.toolbar.visible; 
context: function isPopupWindow() {    return window.toolbar.visible;}
meta: 1705	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/1705/785934168b86472138953b80b4928acf73a171dd/overlay_impl.js/buggy/chrome/content/overlay_impl.js