hild.nodeType)
  testing.expectEqual(9, document.nodeType)
</script>

<script id=ownerDocument>
  let owner = content.ownerDocument;
  testing.expectEqual('HTMLDocument', owner.__proto__.constructor.name);
  testing.expectEqual(null, document.ownerDocument)

  let owner2 = document.createElement('div').ownerDocument;
  testing.expectEqual('HTMLDocument', owner2.__proto__.constructor.name);
</script>

<script id=isConnected>
  testing.expectEqual(true, content.isConnected);
  testing.expectEqual(true, docume