chromium/chrome/test/data/popup_blocker/popup-sessionstorage.html

<html>
<head>
<title>
  Check that the session storage namespace is not accessible to a blocked popup
</title>
<script>
function test() {
  sessionStorage.setItem("key", "set");
  window.open("check-sessionstorage.html");
}
</script>
</head>
<body onload="test()">
pop-up test page
</body>
</html>