mozilla-release/dom/media/webspeech/synth/test/file_bfcache_page1.html

<!DOCTYPE HTML>
<html>
<head>
  <meta charset="utf-8">
  <script type="application/javascript">
    addEventListener('pageshow', function onshow(evt) {
      var u = new SpeechSynthesisUtterance('hello');
      u.lang = 'it-IT-noend';
      u.addEventListener('start', function() {
        location = "file_bfcache_page2.html";
      });
      speechSynthesis.speak(u);
    });
  </script>
</head>
<body>
</body>
</html>