Greesemonkey | Violentmonkey | Tampermonkey | Userscript to force youtube.com to play specific quality (480p, 360p etc)

.user.js

// ==UserScript==
// @name     Youtube 480p
// @version  1
// @grant    none
// @run-at   document-start
// @include     https://www.youtube.com/*
// @version   1.1
// @downloadURL   https://gist.githubusercontent.com/BlurryFlurry/04124b45c0c4ec653cd2dae5a0ed266a/raw/.user.js
// @updateURL   https://gist.githubusercontent.com/BlurryFlurry/04124b45c0c4ec653cd2dae5a0ed266a/raw/.user.js
// ==/UserScript==


(function () {
'use strict';
var d = new Date;
var create = d.getTime();
var expire = d.setFullYear(d.getFullYear() + 1);
  
localStorage.setItem('yt-player-quality','{"data":"large","expiration":' + expire+ ',"creation":'+create+'}');
}());