<!DOCTYPE html>
<html>
<script>
function test() {
    if (window.eventSender) {
        eventSender.mouseMoveTo(100, 100);
        eventSender.continuousMouseScrollBy(0, -10000);
        eventSender.mouseMoveTo(0, 0);
    }
}
</script>
<body onload="test()">
    <select multiple id="sel" style="width:500px; height:300px;"></select>
    <script>
        internals.settings.setScrollAnimatorEnabled(false);
        sel = document.getElementById("sel");
        for (var i = 0; i < 50; i++) {
            option = document.createElement("option");
            option.innerHTML = "Option " + i;
            sel.appendChild(option);
        }
    </script>
</body>
</html>