Mastodon - Add older/newer link

mastodon-add-older-newer-link.user.js

// ==UserScript==
// @name         Mastodon - Add older/newer link
// @namespace    https://github.com/unarist/
// @version      0.2
// @description  Add user timeline link with max_id/min_id to status pages
// @author       unarist
// @downloadURL  https://gist.github.com/unarist/6b445cbb588b405389defb6dbb36e0d9/raw/mastodon-add-older-newer-link.user.js
// @match        https://*/@*/*
// @grant        none
// @noframes
// ==/UserScript==

(function() {
    'use strict';

    const tag = (name, props = {}) => Object.assign(document.createElement(name), props),
          incr = s => s.replace(/(.?)(9*)$/, (_, x, y) => ++x + y.replace(/9/g, 0)),
          decr = s => s.replace(/(.?)(0*)$/, (_, x, y) => --x + y.replace(/0/g, 9)),
          target = document.querySelector('.detailed-status__meta');

    if (!target) return;

    [
        tag('a', { href: location.href.replace(/\d+$/, id => '?max_id=' + incr(id)), textContent: 'older', style: 'margin-left: 1ex; color: inherit' }),
        tag('a', { href: location.href.replace(/\d+$/, id => '?min_id=' + decr(id)), textContent: 'newer', style: 'margin-left: 1ex; color: inherit' }),
    ].forEach(target.appendChild.bind(target));
})();