<!DOCTYPE html>
<html class="reftest-wait">
<style>
#target {
  width: 200vw;
  height: 200vh;
}
</style>
<div id="target"></div>
<script>
const animA = target.animate(
  { transform: 'translateX(100px)' },
  { duration: 50 }
);
const animB = target.animate(
  { transform: 'translateX(100px)', composite: 'add' },
  { duration: 100 }
);
animB.finished.then(() => {
  document.documentElement.classList.remove("reftest-wait");
});
</script>
</html>
