<html>
  <head>
    <script>
      try { o1 = document.createElement('audio') } catch(e) { }
      try { o2 = document.implementation.createDocument('', '', null).adoptNode(o1); } catch(e) { };
      try { o3 = new AudioContext('alarm') } catch(e) { }
      try { o3.createMediaElementSource(o1) } catch(e) { }
    </script>
  </head>
</html>
