headless/test/data/stepper_page.html - chromium/src - Git at Google

 <html>
   <body>
   <div id="box"></div>
   <script>
     let timer_count = 0;
     function callback() {
       document.getElementById('box').textContent = timer_count++;
       window.setTimeout(callback, 1000);
     }
     callback();
   </script>
 </body>
 </html>
	<html>
	<body>
	<div id="box"></div>
	<script>
	let timer_count = 0;
	function callback() {
	document.getElementById('box').textContent = timer_count++;
	window.setTimeout(callback, 1000);
	}
	callback();
	</script>
	</body>
	</html>