chromium/third_party/blink/web_tests/fast/css/sticky/sticky-overflowing.html

<!DOCTYPE html>
<html>
<head>
<style>
    body {
        margin: 0;
        height: 2000px;
        overflow: hidden; /* hide scrollbars */
    }
    
    .container {
        position: absolute;
        width: 200px;
        height: 400px;
        margin: 10px;
        left: 300px;
        top: -200px;
        font-family: Ahem;
        font-size: 24px;
        outline: 2px solid black;
    }
    
    .vertical.container {
        -webkit-writing-mode: vertical-rl;
        top: 300px;
        left: 800px;
        width: 400px;
        height: 200px;
    }
    
    .spacer {
        height: 350px;
        width: 20px;
        background-color: black;
    }
    
    .vertical .spacer {
        height: 20px;
        width: 350px;
    }

    .box {
        width: 150px;
        height: 150px;
    }

    .sticky {
        position: sticky;
        top: 200px;
        right: 200px;
        background-color: green;
        opacity: 0.75;
    }
</style>
<script>
    function doTest()
    {
        window.scrollTo(100, 100);
    }
    window.addEventListener('load', doTest, false);
</script>
</head>
<body>
    <div class="container">
        <div class="spacer"></div>
        <div class="sticky box"></div>
    </div>

    <div class="vertical container">
        <div class="spacer"></div>
        <div class="sticky box"></div>
    </div>
</body>
</html>