chromium/third_party/blink/web_tests/animations/animationworklet/visual-update-expected.html

<!DOCTYPE html>
<style>
#box {
  width: 100px;
  height: 100px;
  background-color: #00ff00;
  transform: translate(0, 100px);
  opacity: 0.5;
  will-change: transform; /* force compositing */
}

#covered {
  width: 100px;
  height: 100px;
  background-color: #ff8080;
}
</style>

<div id="box"></div>
<div id="covered"></div>