The Tor Browser / file revision

 <svg xmlns="http://www.w3.org/2000/svg"

      onload="

         document.documentElement.pauseAnimations();

         document.documentElement.setCurrentTime(0);

         document.getElementById('a').beginElementAt(1);

         document.documentElement.setCurrentTime(2)">

   <!--

     This test case sets up a cycle between simultaneous instance times such that

     when the instance times are sorted if this cycle is not detected we will

     crash.

   -->

   <rect width="100" height="100" fill="red">

     <set attributeName="fill" to="blue" begin="a.begin" dur="4s"/>

     <set attributeName="fill" to="green" id="a"

       begin="b.begin; 3s" dur="4s"/>

     <set attributeName="fill" to="red" id="b"

       begin="a.begin" dur="4s"/>

   </rect>

 </svg>