<!DOCTYPE html>
<html>
<head>
<style>
body, html {
    margin: 0;
}

.cover-block-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 200px;
    height: 200px;
    background-color: black;
}
</style>
</head>
<body>
<img src="../resources/green-400x400.png"></img>
<div class="cover-block-container"></div>
<script>
addEventListener("load", () => {
    let image = document.querySelector("img");
    internals.installImageOverlay(image, [], [
        {
            topLeft : new DOMPointReadOnly(0.1, 0.1),
            topRight : new DOMPointReadOnly(0.4, 0.1),
            bottomRight : new DOMPointReadOnly(0.4, 0.4),
            bottomLeft : new DOMPointReadOnly(0.1, 0.4),
            text : "This is a lot of text that might overflow the overlay block unless we do something about it.",
        }
    ]);
    const block = internals.shadowRoot(image).querySelector("div.image-overlay-block");
    block.style.overflow = "visible";
});
</script>
</body>
</html>