Choose the default resolution for YouTube videos!
Per
// ==UserScript==
// @name Default Resolution - YouTube
// @namespace https://greasyfork.org/en/users/670188-hacker09?sort=daily_installs
// @version 1
// @description Choose the default resolution for YouTube videos!
// @author hacker09
// @match https://m.youtube.com/watch?v=*
// @match https://www.youtube.com/embed/*
// @match https://www.youtube.com/watch?v=*
// @icon https://www.youtube.com/s/desktop/03f86491/img/favicon.ico
// @run-at document-end
// @grant GM_getValue
// @grant GM_setValue
// ==/UserScript==
setTimeout(() => {
'use strict';
if (GM_getValue('Default_Desktop_Resolution') === undefined) //If the Default_Resolution wasn't set yet
{ //Starts the if condition
GM_setValue('Default_Desktop_Resolution', 'hd1080'); //Save the Default YT Desktop Resolution as 1080p
GM_setValue('Default_Mobile_Resolution', 'tiny'); //Save the Default YT Mobile Resolution as 144p
} //Finishes the if condition
if (localStorage.getItem('yt-player-quality') === null || (navigator.userAgentData.mobile === false && (document.getElementById("movie_player").getAvailableQualityLevels().includes(GM_getValue('Default_Desktop_Resolution')) === true && JSON.parse(localStorage.getItem('yt-player-quality'))?.data !== GM_getValue('Default_Desktop_Resolution')))) { //If the user never manually set the resolution before or if the default user resolution exists and if the current video resolution isn't the default user-chosen resolution
localStorage.setItem('yt-player-quality', `{\"data\":\"${(navigator.userAgentData.mobile === true) ? GM_getValue('Default_Mobile_Resolution') : (document.getElementById("movie_player").getAvailableQualityLevels().includes(GM_getValue('Default_Desktop_Resolution')) === true) ? GM_getValue('Default_Desktop_Resolution') : document.getElementById("movie_player").getAvailableQualityLevels()[0]}\",\"expiration\":${new Date().valueOf() + 30 * 24 * 60 * 60 * 1000},\"creation\":${new Date().valueOf()}}`);
location.reload(); //Reloads the page to apply the video resolution
} //Finishes the if condition
}, 800);