<!DOCTYPE html> <!-- webkit-test-runner [ AsyncOverflowScrollingEnabled=true ] -->
<html>
<head>
    <style>
        .container {
            position: relative;
            width: 200px;
            height: 200px;
            margin: 30px;
            border: 1px solid black;
        }
        
        .box {
            width: 100px;
            height: 100px;
            background-color: blue;
            margin: 10px;
        }
        
        .trigger {
            position: absolute;
            left: 20px;
            top: 10px;
            width: 50px;
            height: 50px;
            transform: translateZ(0);
            background-color: gray;
        }
        
        .relative {
            position: relative;
            top: 150px;
            left: 150px;
            z-index: 2;
        }
        
        .interposer {
            position: absolute;
            left: 150px;
            top: 150px;
            background-color: orange;
        }
    </style>
    <script>
        if (window.testRunner)
            testRunner.dumpAsText();

        window.addEventListener('load', () => {
            if (window.internals)
                document.getElementById('layers').textContent = internals.layerTreeAsText(document);
        }, false);
    </script>
</head>
<body>
    <div class="trigger"></div>
    <div class="container">
        <div class="relative box"></div>
    </div>
    <div class="interposer box"></div>
<pre id="layers"></pre>
</body>
</html>