Usersctipt to hide ScuffedUno room code from screen

Hide_ScuffedUNO_Code.user.js

// ==UserScript==
// @name         Hide Scuffed UNO code
// @namespace    http://tampermonkey.net/
// @version      0.0.3
// @description  Hides code from room in scuffeduno.online. Works only on lobby load (do not change code or open it's editor), also do not change window size (not working on mobile)
// @author       NoPlagiarism
// @match        https://scuffeduno.online/menu/room
// @icon         data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==
// @downloadURL  https://gist.githubusercontent.com/NoPlagiarism/1eb53fc26bd2bb35e24cd571f7cf114c/raw/Hide_ScuffedUNO_Code.user.js
// @updateURL    https://gist.githubusercontent.com/NoPlagiarism/1eb53fc26bd2bb35e24cd571f7cf114c/raw/Hide_ScuffedUNO_Code.user.js
// @grant        none
// ==/UserScript==

function waitForElm(selector) {
    // https://stackoverflow.com/questions/5525071/how-to-wait-until-an-element-exists
    return new Promise(resolve => {
        if (document.querySelector(selector)) {
            return resolve(document.querySelector(selector));
        }

        const observer = new MutationObserver(mutations => {
            if (document.querySelector(selector)) {
                observer.disconnect();
                resolve(document.querySelector(selector));
            }
        });

        // If you get "parameter 1 is not of type 'Node'" error, see https://stackoverflow.com/a/77855838/492336
        observer.observe(document.body, {
            childList: true,
            subtree: true
        });
    });
}

function change(elem) {
    'use strict';
    elem.innerHTML = 'Room code: ##CENSORED##';
};

waitForElm('.mt-16 > .text-2xl').then(change);