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Stop autostart videos on youtube
// ==UserScript==
// @author @leoncastro
// @namespace https://github.com/leoncastro
// @name youtube-stop-autostart
// @version 0.02
// @description Stop autostart videos on youtube
// @icon http://s.ytimg.com/yts/img/favicon_48-vfl1s0rGh.png
// @include /^(https?:)?\/\/(www\.)?youtube\.com\/*.*/
// @compatible firefox+greasemonkey
// @compatible chrome+tampermonkey
// @grant none
// @run-at document-end
// ==/UserScript==
// v0.01: document.querySelector('#movie_player').cueVideoByPlayerVars(document.querySelector('#movie_player').getVideoData());
// v0.02:
function ytStopVideo(i){i&&(i=document.querySelector(i))&&i.cueVideoByPlayerVars(i.getVideoData())}
if(/^\/(channel|user)\//i.exec(location.pathname)) // '/channel/CHANNEL_ID' or '/user/UserName'
(new MutationObserver(function(m){ytStopVideo('#c4-player')})).observe(document.querySelector('#upsell-video'),{childList:true});
else // '/watch?v=VIDEO_ID'
ytStopVideo('#movie_player');