scroll-to-text-fragment-scroll-to-center-target.html

<!DOCTYPE html>
<title>
  Ensuring a text directive is scrolled to the center of the view port instead of the top.
</title>
<script src="stash.js"></script>
<script>
function checkScroll() {
  const results = {hasScrolled: window.scrollY != 0};
  let key = (new URL(document.location)).searchParams.get("key");
  stashResultsThenClose(key, results);
};
window.onload = () => {
  window.requestAnimationFrame(function() {
    window.requestAnimationFrame(checkScroll);
  })
}
</script>
<body>
<script>
document.addEventListener("DOMContentLoaded", () => {
  // trigger a layout flush
  _ = document.body.getBoundingClientRect();
});
</script>
<div style="margin-top: 20vh; margin-bottom: 100vh">Scroll to me</div>
</body>

chromium/third_party/blink/web_tests/external/wpt/scroll-to-text-fragment/scroll-to-text-fragment-scroll-to-center-target.html