<!doctype html>
<script>
function boom() {
var r = document.documentElement;
while (r.firstChild) {
r.removeChild(r.firstChild);
}
document.documentElement.contentEditable = "true";
document.documentElement.appendChild(document.createElement("span"));
document.documentElement.firstChild.appendChild(document.createTextNode("_"));
document.execCommand("forwarddelete");
}
</script>
<body onload="boom()">