Test

script.js

// ==UserScript==
// @name Download videos from YouTube
// @description Download videos from YouTube
// @author Makar Lyzhnik
// @version 0.1
// @date 2018-08-13
// @namespace http://googlesystem.blogspot.com
// @include https://www.youtube.com/*
// @match https://www.youtube.com/*
// @match http://s.ytimg.com/yts/jsbin/*
// @connect googlevideo.com
// @connect ytimg.com
// @grant GM_xmlhttpRequest
// @grant GM_getValue
// @grant GM_setValue
// @run-at document-end
// @license MIT License
// @icon data:image/png;base64,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
// ==/UserScript==

(function () {
    var FORMAT_LABEL={'18':'MP4 360p','22':'MP4 720p','43':'WebM 360p','44':'WebM 480p','45':'WebM 720p','46':'WebM 1080p','135':'MP4 480p - no audio','137':'MP4 1080p - no audio','138':'MP4 2160p - no audio','140':'M4A 128kbps - audio','264':'MP4 1440p - no audio','266':'MP4 2160p - no audio','298':'MP4 720p60 - no audio','299':'MP4 1080p60 - no audio'};
    var FORMAT_TYPE={'18':'mp4','22':'mp4','43':'webm','44':'webm','45':'webm','46':'webm','135':'mp4','137':'mp4','138':'mp4','140':'m4a','264':'mp4','266':'mp4','298':'mp4','299':'mp4'};
    var FORMAT_ORDER=['18','43','135','44','22','298','45','137','299','46','264','138','266','140'];
    var FORMAT_RULE={'mp4':'all','webm':'none','m4a':'all'};
    var SHOW_DASH_FORMATS=false;
    var BUTTON_TEXT={'ar':'تنزيل','cs':'Stáhnout','de':'Herunterladen','en':'Download','es':'Descargar','fr':'Télécharger','hi':'डाउनलोड','hu':'Letöltés','id':'Unduh','it':'Scarica','ja':'ダウンロード','ko':'내려받기','pl':'Pobierz','pt':'Baixar','ro':'Descărcați','ru':'Скачать','tr':'İndir','zh':'下载','zh-TW':'下載'};
    var BUTTON_TOOLTIP={'ar':'تنزيل هذا الفيديو','cs':'Stáhnout toto video','de':'Dieses Video herunterladen','en':'Download this video','es':'Descargar este vídeo','fr':'Télécharger cette vidéo','hi':'वीडियो डाउनलोड करें','hu':'Videó letöltése','id':'Unduh video ini','it':'Scarica questo video','ja':'このビデオをダウンロードする','ko':'이 비디오를 내려받기','pl':'Pobierz plik wideo','pt':'Baixar este vídeo','ro':'Descărcați acest videoclip','ru':'Скачать это видео','tr': 'Bu videoyu indir','zh':'下载此视频','zh-TW':'下載此影片'};
    var DECODE_RULE=[];
    var RANDOM=7489235179;
    var CONTAINER_ID='download-youtube-video'+RANDOM;
    var LISTITEM_ID='download-youtube-video-fmt'+RANDOM;
    var BUTTON_ID='download-youtube-video-button'+RANDOM;
    var DEBUG_ID='download-youtube-video-debug-info';
    var STORAGE_URL='download-youtube-script-url';
    var STORAGE_CODE='download-youtube-signature-code';
    var STORAGE_DASH='download-youtube-dash-enabled';
    var isDecodeRuleUpdated=false;  
      
    start();
            
  function start() {
    var pagecontainer=document.getElementById('page-container');
    if (!pagecontainer) return;
    if (/^https?:\/\/www\.youtube.com\/watch\?/.test(window.location.href)) run();       
    var isAjax=/class[\w\s"'-=]+spf\-link/.test(pagecontainer.innerHTML);
    var logocontainer=document.getElementById('logo-container');  
    if (logocontainer && !isAjax) {
      isAjax=(' '+logocontainer.className+' ').indexOf(' spf-link ')>=0;
    }
    var content=document.getElementById('content');
    if (isAjax && content) { // Ajax UI
        var mo=window.MutationObserver||window.WebKitMutationObserver;
        if(typeof mo!=='undefined') {
          var observer=new mo(function(mutations) {
            mutations.forEach(function(mutation) {
                if(mutation.addedNodes!==null) {
                  for (var i=0; i<mutation.addedNodes.length; i++) {
                      if (mutation.addedNodes[i].id=='watch7-main-container') {
                        run();
                        break;
                      }
                  }
                }
            });
          });
          observer.observe(content, {childList: true, subtree: true});
        } else {
          pagecontainer.addEventListener('DOMNodeInserted', onNodeInserted, false);
        }
    } 
  }
  
  function onNodeInserted(e) { 
      if (e && e.target && (e.target.id=='watch7-main-container')) {
        run();
    }
  }
    
  function run() {
    if (document.getElementById(CONTAINER_ID)) return;
  
    var videoID, videoFormats, videoAdaptFormats, videoManifestURL, scriptURL=null;
    var isSignatureUpdatingStarted=false;
    var operaTable=new Array();
    var language=document.documentElement.getAttribute('lang');
    var textDirection='left';
    if (document.body.getAttribute('dir')=='rtl') {
      textDirection='right';
    }
    if (document.getElementById('watch7-action-buttons')) {
      fixTranslations(language, textDirection);
    }
           
    
    var args=null;
    var usw=(typeof this.unsafeWindow !== 'undefined')?this.unsafeWindow:window;
    if (usw.ytplayer && usw.ytplayer.config && usw.ytplayer.config.args) {
      args=usw.ytplayer.config.args;
    }
    if (args) {
      videoID=args['video_id'];
      videoFormats=args['url_encoded_fmt_stream_map'];
      videoAdaptFormats=args['adaptive_fmts'];
      videoManifestURL=args['dashmpd'];
      debug('DYVAM - Info: Standard mode. videoID '+(videoID?videoID:'none')+'; ');
    }
    if (usw.ytplayer && usw.ytplayer.config && usw.ytplayer.config.assets) {
      scriptURL=usw.ytplayer.config.assets.js;
    }  
    
    if (videoID==null) {
      var buffer=document.getElementById(DEBUG_ID+'2');
      if (buffer) {
        while (buffer.firstChild) {
          buffer.removeChild(buffer.firstChild);
        }
      } else {
        buffer=createHiddenElem('pre', DEBUG_ID+'2');
      }    
      injectScript ('if(ytplayer&&ytplayer.config&&ytplayer.config.args){document.getElementById("'+DEBUG_ID+'2").appendChild(document.createTextNode(\'"video_id":"\'+ytplayer.config.args.video_id+\'", "js":"\'+ytplayer.config.assets.js+\'", "dashmpd":"\'+ytplayer.config.args.dashmpd+\'", "url_encoded_fmt_stream_map":"\'+ytplayer.config.args.url_encoded_fmt_stream_map+\'", "adaptive_fmts":"\'+ytplayer.config.args.adaptive_fmts+\'"\'));}');
      var code=buffer.innerHTML;
      if (code) {
        videoID=findMatch(code, /\"video_id\":\s*\"([^\"]+)\"/);
        videoFormats=findMatch(code, /\"url_encoded_fmt_stream_map\":\s*\"([^\"]+)\"/);
        videoFormats=videoFormats.replace(/&amp;/g,'\\u0026');
        videoAdaptFormats=findMatch(code, /\"adaptive_fmts\":\s*\"([^\"]+)\"/);
        videoAdaptFormats=videoAdaptFormats.replace(/&amp;/g,'\\u0026');
        videoManifestURL=findMatch(code, /\"dashmpd\":\s*\"([^\"]+)\"/);
        scriptURL=findMatch(code, /\"js\":\s*\"([^\"]+)\"/);
      }
      debug('DYVAM - Info: Injection mode. videoID '+(videoID?videoID:'none')+'; ');
    }
       
    if (videoID==null) { // if all else fails
      var bodyContent=document.body.innerHTML;  
      if (bodyContent!=null) {
        videoID=findMatch(bodyContent, /\"video_id\":\s*\"([^\"]+)\"/);
        videoFormats=findMatch(bodyContent, /\"url_encoded_fmt_stream_map\":\s*\"([^\"]+)\"/);
        videoAdaptFormats=findMatch(bodyContent, /\"adaptive_fmts\":\s*\"([^\"]+)\"/);
        videoManifestURL=findMatch(bodyContent, /\"dashmpd\":\s*\"([^\"]+)\"/);
        if (scriptURL==null) {
          scriptURL=findMatch(bodyContent, /\"js\":\s*\"([^\"]+)\"/);
          if (scriptURL) {
            scriptURL=scriptURL.replace(/\\/g,'');
          }
        }      
      }
      debug('DYVAM - Info: Brute mode. videoID '+(videoID?videoID:'none')+'; ');
    }