chromium/third_party/blink/web_tests/fast/spatial-navigation/snav-hidden-iframe-zero-size.html

<!DOCTYPE html>
<p>This is <a id="start" href="a">link_1</a>.</p>
  <br>This is <iframe id="1" width=0 height=0 srcdoc="
  <body>
    <a id='11' href='http://a'>b</a>
    <a id='12' href='http://a'>c</a>
    <a id='13' href='http://a'>d</a>
  </body>
  "></iframe><br> an iframe with size 0.<br>
<p>This is <a id="end" href="a">link_2</a>.</p>
<br>
<p>This test is to test that an iframe with size 0 does not get focus, and neither do its descendants.</p>

<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script src="resources/snav-testharness.js"></script>
<script>
  var resultMap = [
    ["Down", "end"]
  ];

  // Start at a known place.
  document.getElementById("start").focus();
  snav.assertFocusMoves(resultMap);
</script>