The Tor Browser / file revision

 <?xml version="1.0"?>

 <svg xmlns="http://www.w3.org/2000/svg" class="reftest-wait">

 <script>

 function boom()

 {

   var animate = document.createElementNS("http://www.w3.org/2000/svg", "animate");

   animate.setAttributeNS(null, "begin", "0.5s");

   document.documentElement.appendChild(animate);

   setTimeout(function() {

     var g = document.createElement("g");

     var svg = document.createElementNS("http://www.w3.org/2000/svg", "svg");

     g.appendChild(svg);

     document.documentElement.appendChild(g);

     svg.setCurrentTime(0.2);

     svg.appendChild(animate);

     svg.setCurrentTime(0.0); // Trigger backwards seek

     document.documentElement.removeAttribute("class");

   }, 400);

 }

 window.addEventListener("load", function() { setTimeout(boom, 200) }, false);

 </script>

 </svg>