>
  <div id="rm"></div>
  <div></div>
  <div id="target"></div>
</div>
<script>
  test(() => {
    assert_equals(getComputedStyle(target).fontWeight, "300");
  }, "Initially, the sibling-index() is 3 for #target");

  test(() => {
    rm.remove();
    assert_equals(getComputedStyle(target).fontWeight, "200");
  }, "Removing a preceding sibling of #target reduces the sibling-index()");

</script>
