An automatic dark/light theme switcher and layout improvement for the gab.com website

gab_theme_switcher.js

// ==UserScript==
// @name         Automatic gab theme switcher
// @namespace    http://tampermonkey.net/
// @version      2025-12-06
// @description  Automatically switch between dark and light themese
// @author       4v3ngR
// @match        https://gab.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=gab.com
// @grant        none
// @run-at       document-start
// ==/UserScript==

(function() {
    'use strict';
    const prefersDarkMode = window.matchMedia("(prefers-color-scheme: dark)");

    const applyTheme = (isDark) => {
        const html = document.querySelector('html');
        if (html) {
            html.setAttribute('theme', isDark ? 'muted' : 'light');
            html.setAttribute('data-theme', isDark ? 'dark' : 'light');
        }
    }

    prefersDarkMode.addEventListener("change", (e) => {
        applyTheme(e.matches);
    });


    window.addEventListener('load', () => {

        setInterval(() => {
            applyTheme(prefersDarkMode.matches);

            if (!document.getElementById('0xdeadbeef')) {
                const style = document.createElement('style');
                style.setAttribute('id', '0xdeadbeef');
                style.innerText = `
                  main { flex-grow: 2 !important; max-width: 100% !important; }
                  main[class="relative"] { justify-content: space-between !important; }
                  main[class="relative"] > div { flex-grow: 999 !important; padding: 0px !important; margin: 0px !important; justify-content: space-between; min-width: 100% !important; }
                  aside { flex-grow: 0 !important; flex-shrink: 1 !important; max-width: 220px !important }
                `;
                document.head.appendChild(style);
            }
        }, 750);
    });
})();