<!DOCTYPE html>
<meta charset="utf8">
<script type="text/javascript">

  var s = `<html><script>
    let result = {
      hardwareConcurrency : navigator.hardwareConcurrency
    };
    window.parent.postMessage(result, "*");`;
  // eslint-disable-next-line
  s += `</` + `script></html>`;

  let b = new Blob([s], { type: "text/html" });
  let url = URL.createObjectURL(b);
  location.href = url;

</script>
<body>
<output id="result"></output>
</body>
