add: var iframe = document.getElementById("Evaluator"); if (iframe.getAttribute("src") != "about:blank") iframe.setAttribute("src", "about:blank"); 
context: function displayResult(){  var resultRange = Evaluator.document.createRange();  resultRange.selectNode(Evaluator.document.documentElement);  var result = resultRange.toString();  if (result)    gConsole.mCService.logStringMessage(result);    // or could use appendMessage which doesn't persist}
meta: 5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5872/0112ac59f855641c9be9ebf24ccb0532fc3ff096/console.js/buggy/xpfe/components/console/resources/content/console.js