<!DOCTYPE html>

<script>

function boom()
{
  var d = document.createElementNS("http://www.w3.org/1999/xhtml", "div");
  d.style.setProperty("-moz-transform", "translate(0pt, 10px)", "");
  d.style.setProperty("opacity", "0.8", "");
  d.style.setProperty("background-color", "gray", "");
  var c = document.createElementNS("http://www.w3.org/1999/xhtml", "canvas");
  (d).appendChild(c);
  (document.body).appendChild(d);
  c.getContext("2d");
}

</script>

<body onload="setTimeout(boom, 100);"></body>