<!DOCTYPE html>
<script>
    onload = function() {
        var elm = document.getElementById('elm');
        document.body.offsetTop; // trigger layout
        elm.style.display = 'block';
    }
</script>
<style>
    .spanner { -webkit-column-span:all; column-span:all; }
</style>
<p>Test insertion of a spanner in the middle of column content, so that we need to split a column row in two.</p>
<p>There should be three lines below with the word "PASS". Letter spacing is expected to vary.</p>
<div style="-webkit-columns:4; -webkit-column-gap:0; width:4em;">
    <div class="spanner">PASS</div>
    <div id="elm" style="display:none;">P<br>A<br>S<br>S</div>
    <div class="spanner">PASS</div>
</div>