g.expectEqual(false, el.matches('#9000'));
  testing.expectEqual(false, el.matches('.notok'));
</script>

<script id=scroll>
  const el3 = document.createElement('div');
  el3.scrollIntoViewIfNeeded();
  el3.scrollIntoViewIfNeeded(false);
  // doesn't throw is good enough
  testing.skip();
</script>

<script id=before>
  const before_container = document.createElement('div');
  document.append(before_container);

  const b1 = document.createElement('div');
  before_container.append(b1);

  const b1_a = docu