<html>
<body>
<svg xmlns="http://www.w3.org/2000/svg" height="100%" width="100%">
<!-- The FO should be visible and completely cover the red rect. -->
<rect id="rect" width="100" height="100" fill="red"/>
<g>
<foreignObject id="fo" width="100" height="100">
<div style="background-color: green; width: 100px; height: 100px;"/>
</foreignObject>
</g>
</svg>
<script>
var pos = Math.round(window.innerWidth * 2 / 3);
document.getElementById('rect').setAttribute('x', pos);
document.getElementById('fo').setAttribute('x', pos);
</script>
</body>
</html>