<!DOCTYPE html>
<html class="reftest-wait">
<head>
<style type="text/css">
#separator-top {
 height: 20px;
 margin-bottom: 10px;
 background-color: green;
}
#overflow {
 overflow: scroll;
 height: 40px;
 margin: 20px 0;
 background-color: green;
}
#separator-bottom {
 height: 20px;
 margin-top: 10px;
 background-color: green;
}
</style>
<script type="text/javascript">
function test() {
 document.getElementById('overflow').style.overflow = 'auto';
 document.documentElement.removeAttribute('class');
}
document.addEventListener('MozReftestInvalidate', test);
</script>
</head>
<body>
<div id="separator-top"></div>
<div id="overflow"></div>
<div id="separator-bottom"></div>
</body>
</html>