Userscript to automate Steam linkfilter

Automate_Steam_linkfilter.user.js

// ==UserScript==
// @name        Automate Steam linkfilter
// @namespace   https://github.com/lense
// @description Skip the Steam link filter on trusted domains
// @include     https://steamcommunity.com/linkfilter/?url=*
// @version     1
// @grant       none
// @run-at document-start
// ==/UserScript==

// Add the Domains you want to be auto-allowed here:
var allowedURLs = new Set(["puu.sh", "tf2r.com", "gist.github.com"])

var filteredURL = window.location.search.substr(5)
var filteredDomain = filteredURL.match("^https?://([^/]*)")[1]
console.log("Testing:", filteredDomain, "in")
console.log(allowedURLs)
if(allowedURLs.has(filteredDomain)) {
  console.log("Domain is allowed. Redirecting to", filteredURL)
  window.location.replace(filteredURL)
} else {
  console.log("Domain is not expressly allowed. You're going to have to click that button yourself.")
}

WHOOPS. Fixed vuln where it would redirect httpS://badwebsite.obscuretld/http://puu.sh