Tampermonkey script to detect rickrolls on reddit

userscript.js

// ==UserScript==
// @name         Rickrolly
// @namespace    http://tampermonkey.net/
// @version      2024-11-21
// @description  You got it
// @author       You
// @match        https://*.reddit.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=github.com
// @grant        none
// ==/UserScript==

(async function () {
  "use strict";

  const selectors = `a[href*='dQw4w9WgXcQ']
a[href*='ub82Xb1C8os']
a[href*='oHg5SJYRHA0']
a[href*='0JgF4CMXU9M']`
    .split("\n")
    .filter((s) => s)
    .map((s) => s + "::after")
    .join(",");

  const head = document.head || document.getElementsByTagName("head")[0];
  const style = document.createElement("style");
  style.id = "detect_rickroll";
  style.appendChild(
    document.createTextNode(
      selectors +
        "{content:'ITS RICK ROLL!!!';font-size:0.6em;vertical-align:super;}"
    )
  );
  head.appendChild(style);
})();