<!DOCTYPE html>
<html>
<head>
<style>

div {
    position: absolute;
    top: 0;
    left: 0;
    width: 100px;
    height: 100px;
    background-color: black;
    will-change: transform;
}

div.changed {
    translate: 100px;
}

</style>
</head>
<body>
<div></div>
<script>
    if (window.testRunner)
        window.testRunner.waitUntilDone();

    requestAnimationFrame(() => {
        document.querySelector("div").classList.add("changed");
        if (window.testRunner)
            window.testRunner.notifyDone();
    });
</script>
</body>
</html>