"></div>

  <div id="expander"></div>

  <script>
    test(function () {
      let root = document.documentElement;
      let body = document.body;
      let content = document.getElementById('content');

      assert_equals(root.offsetWidth, window.innerWidth, "viewport does not show a scrollbar");
      assert_equals(body.offsetWidth, root.offsetWidth, "body matches root");
      assert_equals(content.offsetWidth, body.offsetWidth, "content matches body");
    }, "scrollbar-color auto on the root defers t