<!DOCTYPE HTML>
<html class="reftest-wait">
<head>
<style>
#d {
  transition:opacity 1s;
}
#p {
  position:absolute;
}
</style>
</head>
<body>
<div id="d">
  Hello
  <span id="s"><div id="p">Kitty</div></span>
</div>
<script>
var d = document.getElementById("d");
d.getBoundingClientRect();
d.style.opacity = 0.3;
window.addEventListener("MozReftestInvalidate",
  function() {
    setTimeout(function() {
      document.body.removeChild(d);
      document.documentElement.removeAttribute("class");
    }, 50);
  }, false);
</script>
</body>
</html>