composited-sticky-overflow-padding.html

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

.scroller {
  height: 200px;
  width: 100px;
  overflow-y: scroll;
  padding: 20px 0;

  /* Force compositing. */
  backface-visibility: hidden;
}

.contents {
  height: 500px;
  width: 100%;
}

.prepadding {
  height: 100px;
  width: 100%;
}

.container {
  height: 300px;
  width: 100%;
}

.filler {
  height: 100px;
  width: 100%;
}

.sticky {
  height: 100px;
  width: 100%;
  background-color: green;
  position: sticky;
  top: 50px;
}
</style>

<div class="scroller">
  <div class="contents">
    <div class="prepadding"></div>
    <div class="container">
      <div class="filler"></div>
      <div class="sticky"></div>
    </div>
  </div>
</div>

<script>
if (window.testRunner)
  testRunner.waitUntilDone();

function finishTest() {
  document.querySelector('.scroller').scrollTop = 200;
  if (window.testRunner)
    testRunner.notifyDone();
}

window.addEventListener('load', function() {
  requestAnimationFrame(function() {
    requestAnimationFrame(finishTest);
  });
});
</script>

chromium/third_party/blink/web_tests/compositing/overflow/composited-sticky-overflow-padding.html