LayoutTests/fast/repaint/overflow-flipped-writing-mode-block-in-regions.html

<script src="resources/repaint.js"></script>
<script>
    if (window.testRunner)
        window.testRunner.overridePreference("WebKitCSSRegionsEnabled", "1");
    onload = runRepaintTest;

    function repaintTest()
    {
        document.getElementById("target").style.visibility = "hidden";
    }
</script>
<div style="-webkit-flow-into: thread; height: 100px; width: 100px; background-color: red; -webkit-writing-mode: horizontal-bt;">
    <div style="height: 25px;">
        <div style="height: 100px; background-color: green;"></div>
    </div>
</div>
<div id="target" style="-webkit-flow-into: thread; height: 50px; width: 100px; background-color: red; margin-top: -100px;"></div>
<div style="-webkit-flow-from: thread; width:100px;height:400px; border:2px solid black; position:absolute; left:100px; top:100px"></div>