Youtube H.264

use H.264 on youtube. based on https://github.com/erkserkserks/h264ify.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         Youtube H.264
// @namespace    http://www.youtube.com
// @version      1.1.2
// @description  use H.264 on youtube. based on https://github.com/erkserkserks/h264ify.
// @match        http://youtube.com/*
// @match        https://youtube.com/*
// @match        http://www.youtube.com/*
// @match        https://www.youtube.com/*
// @grant        none
// @run-at       document-start
// ==/UserScript==


// code from https://github.com/erkserkserks/h264ify/blob/master/src/inject/inject.js

var h264ify = function () {
    // Override video element canPlayType() function
    var videoElem = document.createElement('video');
    var origCanPlayType = videoElem.canPlayType.bind(videoElem);
    videoElem.__proto__.canPlayType = function (type) {
        if (type === undefined) return '';
        // If queried about webM/vp8/vp8 support, say we don't support them
        if (type.indexOf('webm') != -1
            || type.indexOf('vp8') != -1
            || type.indexOf('vp9') != -1) {
            return '';
        }
        // Otherwise, ask the browser
        return origCanPlayType(type);
    }
    
    // Override media source extension isTypeSupported() function
    var mse = window.MediaSource;
    var origIsTypeSupported = mse.isTypeSupported.bind(mse);
    mse.isTypeSupported = function (type) {
        if (type === undefined) return '';
        // If queried about webM/vp8/vp8 support, say we don't support them
        if (type.indexOf('webm') != -1
            || type.indexOf('vp8') != -1
            || type.indexOf('vp9') != -1) {
            return '';
        }
        // Otherwise, ask the browser
        return origIsTypeSupported(type);
    }
};

h264ify();