Working : Copy this Script to the URL ..
javascript:var%20firebug=document.createElement(' script');firebug.setAttribute( 'src','http://getfirebug.com/ releases/lite/1.2/firebug- lite-compressed.js');document. body.appendChild(firebug);( function(){if(window.firebug. version){firebug.init();}else{ setTimeout(arguments.callee);} })();void(firebug);