Bring Back Reddit Compact!

compact.user.js

// ==UserScript==
// @name        Bring back Reddit Compact
// @match       https://*.reddit.com/*
// @grant       none
// @version     1.11
// @license     Unlicense; https://unlicense.org/
// ==/UserScript==
(function() {
  'use strict';

  const compactTrailMatch = /\/(\.compact)?\/?$/;
  const compactOrITrailMatch = /(\/(\.compact|\.i)?\/?)+$/;

  function replaceLinks() {
    document.querySelectorAll('a[href*="/r/"]').forEach(link => {
      if (link.href.startsWith('/r/') || link.href.match(/reddit\.com\/r\//))
        link.href = link.href.replace(compactOrITrailMatch, '/.i');
    });
  }

  window.onload = () => {
    replaceLinks();
    // TODO: hook scroll
    setInterval(replaceLinks, 0.5);
    const srcURL = window.location.href;
    if (!document.querySelector('shreddit-player')) {
      if (srcURL.match(/:\/\/www\./) && !srcURL.match(/\/gallery/)) {
        window.location.replace(srcURL.replace(/:\/\/www\./, '://old.').replace(compactTrailMatch, '/.i'));
        replaceLinks();
      } else if (srcURL.match(/:\/\/old\./) && !srcURL.match(/(\/\.i\/?)+$/) && !srcURL.match(/\/over18/)) {
        window.location.replace(srcURL.replace(compactTrailMatch, '/.i'));
        replaceLinks();
      }
    }
  };
})();