<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<body>
The two green blocks below should be identical and should each take up half the width of the browser window.
<div style="border:1px solid black; width:50%; height:500px; background-color:green; float:right; -webkit-box-sizing:border-box;"></div>
<div style="border:1px solid black; width:50%; height:500px; background-color:green; overflow:hidden; -webkit-box-sizing:border-box;"></div>
</body>
</html>