<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script>
function test()
{
    if (window.testRunner)
        testRunner.dumpAsText();
    document.getElementById("result").firstChild.data = 'SUCCESS!';

    var ruby = document.getElementById('R');
    var span = document.getElementById('S');
    var newRT = document.createElement('rt');
    var newRTText = document.createTextNode('new ruby text');
    newRT.appendChild(newRTText);
    ruby.insertBefore(newRT, span);    
}
</script>
</head>
<!-- Inserting a <rt> element, causing a split of block flow to block flow and block flow -->
<!-- As this is a malformed example we don't care about the exact rendering output, only that it doesn't crash -->
<body onload="test()">
<div id="result">FAILED!</p>
<br>
<br>
<ruby id="R">text <div>block</div> <span id="S">more</span> <div>text</div><rt>ruby text</rt></ruby>
</body>
</html>