css/cssom-view/offsetParent-block-in-inline.html

<!DOCTYPE html>
<link rel="help" href="https://drafts.csswg.org/cssom-view-1/#extensions-to-the-htmlelement-interface">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<span id="parent" style="position:relative;">
    <div id="target"></div>
</span>
<script>
test(function() {
  const target = document.getElementById('target');
  const parent = document.getElementById('parent');
  assert_equals(target.offsetParent, parent);
});
</script>