:focus {
    background-color: blue;
  }
</style>
<div id="scroller">
  <div id="target"></div>
  <div></div>
</div>
<script>
  promise_test(async t => {
    actions_promise = new test_driver.Actions()
      .pointerMove(15, 15)
      .pointerDown()
      .pointerUp()
      .send();
    await actions_promise;
    assert_equals(getComputedStyle(target, "::scroll-marker").backgroundColor, "rgb(0, 0, 255)", "::scroll-marker activation retains focus");
  });
</script>