Hide HDR support from YouTube

Hide HDR support for Firefox 69. v0.1 2019-10-10

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 or Violentmonkey 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        Hide HDR support from YouTube
// @author      Jefferson "jscher2000" Scher
// @namespace   JeffersonScher
// @version     0.1
// @copyright   Copyright 2019 Jefferson Scher
// @license     BSD-3-Clause
// @description Hide HDR support for Firefox 69. v0.1 2019-10-10
// @match       https://www.youtube.com/*
// @match       https://www.youtube-nocookie.com/*
// @match       https://www.youtu.be/*
// @run-at      document-start
// @grant       none
// ==/UserScript==

var mse = window.MediaSource;

if (mse){
  // Set up replacement for MediaSource type support function
  var nativeITS = mse.isTypeSupported.bind(mse);
  mse.isTypeSupported = ourITS(nativeITS);
}

// Here's the replacement
function ourITS(fallback){
  // type is a string (hopefully!) sent by the page
  return function (type) {
    if (type === undefined) return '';
    //console.log('testing for: '+ type);

    // Don't support HDR (current as of 10/10/2019)
    if (type.toLowerCase().indexOf('eotf=bt709') > -1 ||
        type.toLowerCase().indexOf('eotf=catavision') > -1) return '';

    // Uncomment to block all VP9 (if performance is bad)
    //if (type.toLowerCase().indexOf('vp9') > -1) return '';

    // Let Firefox handle everything else
    return fallback(type);
  };
}