Improve YouTube Transcript for Language learning

Improved YouTube Transcript for Language learning, click transcript to hide the element below the video.
目前為 2016-09-16 提交的版本，檢視最新版本。
安裝腳本 ?
換行
// ==UserScript==
// @name         Improve YouTube Transcript for Language learning
// @namespace    http://tampermonkey.net/
// @version      0.2
// @description  Improved YouTube Transcript for Language learning, click transcript to hide the element below the video.
// @author       AVES
// @include      http*://*.youtube.com/watch*
// @include      http*://youtube.com/watch*
// @run-at       document-end
// ==/UserScript==
start();
function add(){
        var $bar = document.getElementById("watch8-secondary-actions");
        var $newButton= document.createElement('div');
        $newButton.className="yt-uix-menu ";
        var $transcriptButton=document.createElement("button");
        $transcriptButton.className="yt-ui-menu-item has-icon yt-uix-menu-close-on-select action-panel-trigger action-panel-trigger-transcript";
        var $label=document.createElement("span");
        $label.className="yt-ui-menu-item-label";
        var $textTranscript = document.createTextNode("Transcript");
        $bar.appendChild($newButton);
        $newButton.appendChild($transcriptButton);
        $transcriptButton.appendChild($label);
        $label.appendChild($textTranscript);
        $transcriptButton.setAttribute("data-trigger-for","action-panel-transcript");

        var $windowTranscript=document.getElementById("watch-actions-transcript");
        var $h2Transcript= document.getElementsByClassName("yt-card-title");
        var $title=document.getElementById("watch-header");
        $transcriptButton.onclick=function(){
            $title.style.display="none";
            var sheet = document.createElement("STYLE");
            var t = document.createTextNode(".caption-line-time { display: none; }.caption-line-text { width: 100%; }");
            sheet.appendChild(t);
            document.head.appendChild(sheet);
            $h2Transcript[0].style.float="right";
            $h2Transcript[0].style.padding="0 10px";
            var $close= document.getElementById("action-panel-dismiss");



            setTimeout(function(){$close.onclick=function(){$title.style.display="block";};},10);



        };
    }



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) { // fix for blocked videos
        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-container' ||
                                mutation.addedNodes[i].id=='watch7-main-container') { // old value: movie_player
                                run();
                                break;
                            }
                        }
                    }
                });
            });
            observer.observe(content, {childList: true, subtree: true}); // old value: pagecontainer
        } else { // MutationObserver fallback for old browsers
            pagecontainer.addEventListener('DOMNodeInserted', onNodeInserted, false);
        }
    }
}

function onNodeInserted(e) {
    if (e && e.target && (e.target.id=='watch7-container' ||
                          e.target.id=='watch7-main-container')) { // old value: movie_player
        run();
    }
}

function finalButton(){

    var buttonIframeDownload = document.createElement("iframe");
    buttonIframeDownload.src = '//www.youtubeinmp3.com/widget/button/?color=ba1717&amp;video=' + window.location.href;
    buttonIframeDownload.scrolling = "no";
    buttonIframeDownload.id = "buttonIframe";
    buttonIframeDownload.style = "width:100%;height:60px;padding-top:20px;padding-bottom:20px;";

    document.getElementById("watch-header").appendChild(buttonIframeDownload);

}

function run(){

    if(!document.getElementById("parentButton") && window.location.href.substring(0, 25).indexOf("youtube.com") > -1 && window.location.href.indexOf("watch?") > -1){

        var parentButton = document.createElement("div");

        parentButton.className = "yt-uix-button yt-uix-button-default";
        parentButton.id = "parentButton";
        parentButton.style = "height: 23px;margin-left: 28px;padding-bottom:1px;";

        parentButton.onclick = function () {

            this.style = "display:none";
            finalButton();

        };

        document.getElementById("watch7-user-header").appendChild(parentButton);

        var childButton = document.createElement("span");

        childButton.appendChild(document.createTextNode("Download MP3"));

        childButton.className = "yt-uix-button-content";
        childButton.style = "line-height: 25px;font-size: 12px;";

        parentButton.appendChild(childButton);
        add();

    }

}