Tools/TestWebKitAPI/Tests/WebKitCocoa/postMessage-regularly.html - WebKit - Git at Google

 <!DOCTYPE>
 <html>
 <body>
 <script>
 setInterval(() => {
     webkit.messageHandlers.testHandler.postMessage('timer fired');
 }, 5);
 </script>
 </body>
 </html>
	<!DOCTYPE>
	<html>
	<body>
	<script>
	setInterval(() => {
	webkit.messageHandlers.testHandler.postMessage('timer fired');
	}, 5);
	</script>
	</body>
	</html>