ss13_userscript.js

// ==UserScript==
// @name         r/ss13 Logo template
// @match        https://hot-potato.reddit.com/embed*
// ==/UserScript==
if (window.top !== window.self) {
    window.addEventListener('load', () => {
        document.getElementsByTagName("mona-lisa-embed")[0].shadowRoot.children[0].getElementsByTagName("mona-lisa-canvas")[0].shadowRoot.children[0].appendChild(
            (function () {
                const i = document.createElement("img");
                i.src = "https://mocha.affectedarc07.co.uk/placemap.png";
                i.style = "position: absolute;right: 0;top: 0;image-rendering: pixelated;width: 2000px;height: 1000px;";
                console.log(i);
                return i;
            })())
    }, false);
}