anchor-scroll-to-sticky-001-ref.html

<!DOCTYPE html>
<style>
body {
  margin: 0;
}

div {
  width: 100px;
  height: 100px;
}

#scroller {
  overflow: scroll;
}

#anchor {
  height: 20px;
  background: orange;
}

#anchored {
  position: absolute;
  top: 20px;
  left: 0;
  background: green;
}

</style>

<div id="scroller">
  <div style="height: 200px"></div>
  <div id="anchor"></div>
  <div style="height: 150px"></div>
</div>
<div id="anchored"></div>

<script>
scroller.scrollTop = 200;
</script>

chromium/third_party/blink/web_tests/external/wpt/css/css-anchor-position/reference/anchor-scroll-to-sticky-001-ref.html