rem: openNewTabWith(frameURL, null, null, null, false, makeURI(doc.referrer)); 
add: openNewTabWith(frameURL, null, null, null, false, referrer ? makeURI(referrer) : null); 
context:   openFrameInTab: function() {    var doc = this.target.ownerDocument;    var frameURL = doc.documentURIObject.spec;    openNewTabWith(frameURL, null, null, null, false, makeURI(doc.referrer));  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/9421/91ac5d2ea7b84bd79affaf38d95d9497d129d150/nsContextMenu.js/buggy/browser/base/content/nsContextMenu.js