F12を押して以下を打ち込め。
alert("hello"); w=window.open("","title","width=500px,height=300px"); w.document.write("hello<br>"); w.document.write("<input id='b1' type=button value=test><br>"); w.document.getElementById("b1").onclick=function(){ w.document.write("hello<br>"); }; w.document.write("<input id='t1' type=text value=''><br>"); w.document.getElementById("b1").onclick=function(){ w.document.write("hello " + w.document.getElementById("t1").value + "<br>"); }; i=0; setInterval(function(){body.style.transform = "rotate(" + i + "deg)"; i++;}, 100);