third_party/WebKit/LayoutTests/imported/wpt/service-workers/service-worker/resources/client-navigate-frame.html - chromium/src - Git at Google

 <!DOCTYPE html>
 <meta charset=utf-8>
 <script>
   fetch("clientId")
     .then(function(response) {
       return response.text();
     })
     .then(function(text) {
       parent.postMessage({id: text}, "*");
     });
 </script>
 <body style="background-color: red;"></body>
	<!DOCTYPE html>
	<meta charset=utf-8>
	<script>
	fetch("clientId")
	.then(function(response) {
	return response.text();
	})
	.then(function(text) {
	parent.postMessage({id: text}, "*");
	});
	</script>
	<body style="background-color: red;"></body>