Fix YouTube's Alt-Tab Pause/Play Issue

FixYoutubeAltTabPlayPauseIssue.user.js

// ==UserScript==
// @name         Fix YouTube's Alt-Tab Pause/Play Issue
// @namespace    http://tampermonkey.net/
// @version      0.4
// @description  Fix YouTube's Alt-Tab Pause/Play Issue
// @author       HPZ07
// @match        https://www.youtube.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=youtube.com
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    window.addEventListener('keyup', keyHandler);
    window.addEventListener('keydown', keyDownHandler);
    const nonTriggerableElements = ['search', 'contenteditable-root', 'gsfi ytd-searchbox', 'ytd-searchbox', 'style-scope yt-formatted-string'];

    let video = document.querySelector('video');
    let videoState;

    function canTriggerSpaceAction() {
        return !nonTriggerableElements.some(element => {
            return document.activeElement.matches(`.${element}`) || document.activeElement.id === element;
        });
    }

    function keyHandler(e) {
        if (!canTriggerSpaceAction() || e.code !== 'Space' || !isWatchPage) return;
        video = document.querySelector('video');
        if (videoState === "play") video.play();;
        if (videoState === "pause") video.pause();
    }

    function keyDownHandler(e) {
        if(!isWatchPage) return;
        videoState = video.paused ? "play" : "pause";
        keyHandler(e);
    }

    function isWatchPage() {
        return /^\/watch/.test(location.pathname);
    }

})();

Thanks! I've updated the @match as suggested.

the fix was to change the @match line to

// @match        *://*.youtube.com/watch*

I needed this script so much. Not sure what changed on YouTube, but this started to annoy me to no end.

Thanks! I've updated the @match as suggested.

the fix was to change the @match line to

// @match        *://*.youtube.com/watch*

nevermind, tampermonkey is again not loading the script on youtube watch pages

weird, if i change it to

// @match        *://*.youtube.com/watc*

it suddenly starts working again

nevermind, tampermonkey is again not loading the script on youtube watch pages

It works on my end simply by refreshing the watch page.

0.4 should fix the problem(hopefully). Using a wildcard character on YouTube (e.g., watch*) may not be ideal due to YouTube's asynchronous content loading.

function isWatchPage() {
     return /^\/watch/.test(location.pathname);
}

If you open a video in a new tab and the first thing you do is Alt+Tab, it won't register the first space but will after that.

The space bar doesn't work correctly on embedded videos. You should exclude them with this line:

// @exclude https://www.youtube.com/embed/*

Awesome script! Thanks @HPZ07 !

Big Thanks