<!DOCTYPE html>
<html class='reftest-wait'>
  <head>
    <style>
      fieldset:invalid { display: none; }
    </style>
  </head>
  <script>
    function onloadHandler()
    {
      document.getElementById('i').readOnly = false;
      document.documentElement.className = '';
    }
  </script>
  <body onload='onloadHandler();'>
    <fieldset id="fieldset">
      <input id='i' required readonly>
    </fieldset>
  </body>
</html>