etElementById('testOpener');
            elm.textContent = String(window.opener);
          })();
        </script>
      </li>

      <li>
        <strong>user object</strong>
        <code>
          <span id="testUserObject"></span>
        </code>
        <script>
          userObject = {};
        </script>
        <script type="text/partytown">
          (async function () {
            const elm = document.getElementById('testUserObject');
            elm.textContent = String(window.userObject);
    