<!DOCTYPE html>
<html class="reftest-wait">
<head>
<canvas id="canvas" width="150" height="150"></canvas>

<script>

var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
ctx.transform(1,0.5,-0.5,1,30,10);
setTimeout(function() {
  var canvas = document.getElementById('canvas');
  var ctx = canvas.getContext('2d');
  var transform = ctx.mozCurrentTransformInverse;
  ctx.mozCurrentTransformInverse = transform;
  ctx.fillStyle = '#f00';
  ctx.fillRect(0, 0, 100, 100);
  document.documentElement.removeAttribute("class");
}, 10)

</script>
</body></html>