<!DOCTYPE html>
<p>There should be a blue <em>square</em> below.</p>
<div style="-webkit-columns:2; width:100px; background:blue;">
    <div id="container" style="position:relative;">
        <div style="-webkit-column-span:all; margin-bottom:100px;"></div>
        <div style="position:absolute;"></div>
        <div style="-webkit-column-span:all; margin-top:100px;"></div>
    </div>
</div>
<script>
    document.body.offsetTop;
    document.getElementById('container').style.position = 'static';
</script>