Gmail's Google Chat Dark Mode

google-chat-dark-mode.user.js

// ==UserScript==
// @name        Google Chat Dark Theme
// @namespace   https://mail.google.com/mail/u/0/
// @version     1.0.3
// @description Change the Google Chat theme in Gmail
// @author      GH - @bgbrwr
// @match       https://chat.google.com/u/0/frame?shell=6&pt=15&origin=https%3A%2F%2Fmail.google.com*
// @icon        https://www.google.com/s2/favicons?sz=64&domain=google.com
// @grant       none
// @updateURL   https://gist.githubusercontent.com/BGBRWR/4279964f21a7b1bda05aa22d0506f477/raw/google-chat-dark-mode.user.js
// @downloadURL https://gist.githubusercontent.com/BGBRWR/4279964f21a7b1bda05aa22d0506f477/raw/google-chat-dark-mode.user.js
// ==/UserScript==

(function() {
    'use strict';
        // Check if the script is running in the iframe and not the top window
    if (window.self !== window.top) {
        document.body.setAttribute("data-theme", "dark");
    }
})();