<html>
<head>
<script>
function start () {
  const frame = document.createElementNS('http://www.w3.org/1999/xhtml', 'frame')
  document.documentElement.appendChild(frame)
  frame.contentWindow.eval('window.top.context=new AudioContext()')
  document.documentElement.innerHTML = ''
  context.createMediaElementSource(new Audio(''))
}

document.addEventListener('DOMContentLoaded', start)
</script>
</head>
</html>
