third_party/blink/web_tests/animations/animationworklet/visual-update-expected.html - chromium/src - Git at Google

 <!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>
	<!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>