composited-bounds-for-negative-z.html

<!DOCTYPE html>
<div style="will-change: transform;
            height: 10px;
            width: 10px;
            position: absolute;
            background-color: red;
            z-index: -1"></div>
<div style="margin-left: 100px;
            margin-top: 100px;
            height: 300px;
            width: 300px;
            overflow-y: scroll;">
    <div style="position: relative">
        <div style="position: relative;
                    height: 1000px;
                    background-color: lightblue">
        </div>
    </div>
</div>
<script>
if (window.testRunner) {
    testRunner.dumpAsText();
    internals.settings.setPreferCompositingToLCDTextEnabled(true);
    testRunner.setCustomTextOutput(internals.layerTreeAsText(document));
}
</script>

chromium/third_party/blink/web_tests/compositing/squashing/composited-bounds-for-negative-z.html