cript type="text/javascript">
  'use strict';

  promise_test(async t => {
    await waitForCSSScrollTimelineStyle();
    const scroller = document.querySelector('.scroller');
    assert_equals(getComputedStyle(scroller, ':before').backgroundColor,
                  'rgb(0, 0, 255)');
  }, `view() on pseudo-element attaches to parent scroll container`);
</script>
</html>
