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YouTube - Add "Stop Video" Button

Adds a 'Stop Video' button below the video

// ==UserScript==
// @name            YouTube - Add "Stop Video" Button
// @namespace       https://greasyfork.org/en/users/321-joesimmons
// @description     Adds a 'Stop Video' button below the video
// @include         http://*.youtube.com/watch*v=*
// @include         https://*.youtube.com/watch*v=*
// @include         http://youtube.com/watch*v=*
// @include         https://youtube.com/watch*v=*
// @include         http://youtube.com/user/*
// @include         https://youtube.com/user/*
// @include         http://youtube.com/channel/*
// @include         https://youtube.com/channel/*
// @include         http://*.youtube.com/user/*
// @include         https://*.youtube.com/user/*
// @include         http://*.youtube.com/channel/*
// @include         https://*.youtube.com/channel/*
// @copyright       JoeSimmons
// @version         1.1.0
// @license         GPL version 3 or any later version; http://www.gnu.org/copyleft/gpl.html
// @require         https://greasyfork.org/scripts/2104-youtube-button-container-require/code/YouTube%20-%20Button%20Container%20(@require).js?version=5493
// @grant           GM_addStyle
// ==/UserScript==

/* CHANGELOG

    1.1.0 (12/13/2013)
        - changed license to GPLv3

    1.0.9 (12/13/2013)
        - started using my new @require for adding buttons to the page

    1.0.8 (12/11/2013)
        - started adding the stop button to a div under the movie player
            so other scripts can use that space to add buttons to also

    1.0.7 (11/23/2013)
        - fixed something I missed in 1.0.6

    1.0.6 (11/23/2013)
        - adapted to site change

    1.0.5 (9/6/2013)
        - made it work on user/channel pages

    1.0.4 (9/1/2013)
        - made it support the YouTube 'red bar' feature

    1.0.3 (8/31/2013)
        - included https pages

    1.0.2 (8/30/2013)
        - now supports native Chrome & Opera

    1.0.1
        - made it more cross-browser compatible

    1.0.0
        - created

*/

(function () {
    'use strict';

    var verif = /youtube\.com\/((watch\?[a-zA-Z]+=)|(user|channel))/,
        button_id = 'movie_stop_button';

    function run(t) {
        var s = document.createElement('script');
            s.innerHTML = t;
        document.body.appendChild(s);
        document.body.removeChild(s);
    }

    function stopVideo() {
        run('' +
            '(function () {' +
                'var player = document.querySelector("#c4-player, #movie_player");' +
                'if (player.stopVideo) {' +
                    'player.stopVideo();' +
                '} else if (player.pauseVideo) {' +
                    'player.pauseVideo();' +
                '} else if (player.pause) {' +
                    'player.pause();' +
                '}' +
            '}());' +
        '');
    }

    function addButton() {
        var button = document.getElementById(button_id);

        if (button == null) {
            addButtonToContainer('Stop Video', stopVideo, button_id);
        }
    }

    // make sure the page is not in a frame
    if (window !== window.top) { return; }

    window.setInterval(addButton, 1000);

}());