<?xml version="1.0" encoding="utf-8"?>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Feedback image and border-radius</title>
<style type="text/css">
body
  {background-color:silver;
  margin:0;}
div
  {background-color:white;}
div > div
  {display:block;
  width:100px;
  height:100px;
  border:solid thin green;
  border-radius:50px;}
</style>
</head>
<body>
<div>
  <div draggable="true" ondragstart="event.dataTransfer.effectAllowed = 'copy'"/>
</div>
<p>Try to drag green circle above. Feedback overlay should be a circle.</p>
</body>
</html>