chromium/components/test/data/ad_tagging/abort_regression.html

<!DOCTYPE html>
<html>
<head>
<script>
  window.onload = () => {
    // Don't block on async function completing.
    (async function () {
      // Wait so that the initial top-level navigation is completely committed.
      await new Promise(resolve => setTimeout(resolve, 0));

      // Set up history entries.
      await iframe.contentWindow.navigation.navigate("#").finished;
      await navigation.navigate("#").finished;

      // Prevent the top-level frame from finishing its navigation too quickly.
      navigation.onnavigate = e => e.preventDefault();

      // Undo the iframe navigation; this also undoes the top-frame navigation.
      iframe.contentWindow.navigation.back();
    })();
  }
</script>
</head>

<body>
  <iframe id="iframe" src="blank.html"></iframe>
</body>

</html>