<!DOCTYPE html>

<html>
<head>
    <style>
        body {
            height: 2000px;
            margin: 0;
        }
        .fixed {
            position: fixed;
            top: 200px;
            height: 200px;
            width: 100%;
            background-color: green;
        }
    </style>
    <script>
        window.addEventListener('load', () => {
            internals.unconstrainedScrollTo(document.scrollingElement, 0, -100);
        }, false);
    </script>
</head>
<body>

<div class="fixed"></div>

</body>
</html>