chromium/src/third_party/blink/web_tests/intersection-observer/resources/iframe-that-shares-observer.html - manifest_repos/chromium_src - Git at Google

 <body>
 <div id="root">
 <div id="child"></div>
 </div>
 <script>
 var o = new IntersectionObserver(function(){}, {root: root});
 o.observe(child);
 parent.move(root);
 </script>
 </body>
	<body>
	<div id="root">
	<div id="child"></div>
	</div>
	<script>
	var o = new IntersectionObserver(function(){}, {root: root});
	o.observe(child);
	parent.move(root);
	</script>
	</body>