tent.tagName);
  testing.expectEqual('content', content.id);

  content.id = 'foo';
  testing.expectEqual('foo', content.id);

  content.id = 'content';
  testing.expectEqual('', content.className);

  let p1 = document.getElementById('para-empty');
  testing.expectEqual('ok empty', p1.className);

  p1.className = 'foo bar baz';
  testing.expectEqual('foo bar baz', p1.className);

  p1.className = 'ok empty';
  testing.expectEqual(2, p1.classList.length);
</script>

<script id=closest>
  const el2 = docume