replace-x-copy-link.user.js

// ==UserScript==
// @name         Replace x.com Copy Link Domain
// @version      1.0
// @description  Intercept "Share > Copy link" on X (Twitter) and replace domain (x.com/twitter.com → custom mirror)
// @author       Eszee
// @match        https://twitter.com/*
// @match        https://x.com/*
// @icon         https://abs.twimg.com/favicons/twitter.2.ico
// @updateURL    https://gist.github.com/Suznyan/7e9443c88570a02e257887f259570641/raw/f644af9b3ab68e2613db06981460c889774e29bb/replace-x-copy-link.user.js
// @downloadURL  https://gist.github.com/Suznyan/7e9443c88570a02e257887f259570641/raw/f644af9b3ab68e2613db06981460c889774e29bb/replace-x-copy-link.user.js
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    /* ==============================
       🔧 CONFIGURATION
       ============================== */
    const REPLACEMENT_DOMAIN = 'fxtwitter.com';
    // 👉 Change this to whatever mirror you want, e.g.:
    // const REPLACEMENT_DOMAIN = 'cunnyx.com';

    const MATCH_REGEX = /https?:\/\/(www\.)?(x|twitter)\.com/ig;
    const REPLACEMENT_BASE = `https://${REPLACEMENT_DOMAIN}`;

    /* ==============================
       🚀 CORE LOGIC
       ============================== */

    // Replace x.com/twitter.com → chosen mirror domain
    function rewriteUrl(text) {
        if (typeof text !== 'string') return text;
        return text.replace(MATCH_REGEX, REPLACEMENT_BASE);
    }

    // Patch clipboard API used by “Copy link”
    function patchClipboard() {
        if (!navigator.clipboard || !navigator.clipboard.writeText) return;

        const originalWriteText = navigator.clipboard.writeText.bind(navigator.clipboard);
        navigator.clipboard.writeText = async function(text) {
            const newText = rewriteUrl(text);
            return originalWriteText(newText);
        };
    }

    // Also handle manual copy (Ctrl+C / context menu)
    function handleCopyEvent(e) {
        try {
            const sel = document.getSelection();
            const text = sel ? sel.toString() : '';
            if (MATCH_REGEX.test(text)) {
                const replaced = rewriteUrl(text);
                e.clipboardData.setData('text/plain', replaced);
                e.preventDefault();
            }
        } catch {}
    }

    function init() {
        patchClipboard();
        document.addEventListener('copy', handleCopyEvent, true);
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', init);
    } else {
        init();
    }
})();