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Youtube: Spacebar to Play/Pause Videos

Force bind the spacebar to play/pause videos

// ==UserScript==
// @name         Youtube: Spacebar to Play/Pause Videos
// @namespace    ytSpacePauseKK
// @description  Force bind the spacebar to play/pause videos
// @version      1.7
// @author       Kai Krause <kaikrause95@gmail.com>
// @match        http://*.youtube.com/*
// @match        https://*.youtube.com/*
// @exclude      https://*.youtube.com/embed/*
// @run-at       document-start
// @grant        none
// ==/UserScript==

let cachedMode = "";
document.addEventListener("keydown", function onEvent(e) {
	if (e.code !== "Space") return;

	let ae = document.activeElement;
	if (ae.tagName.toLowerCase() == "input" || ae.hasAttribute("contenteditable")) return;
	e.preventDefault();
	e.stopImmediatePropagation();

	if (document.location.hostname == "music.youtube.com") {
		document.querySelector("#play-pause-button").click();
	}
	else {
		let player = document.querySelector(".html5-video-player");
		if (player.classList.contains("paused-mode")) cachedMode = "paused-mode";
		if (player.classList.contains("playing-mode")) cachedMode = "playing-mode";
		if (player.classList.contains("ended-mode")) cachedMode = "ended-mode";

		setTimeout(() => {
			let player = document.querySelector(".html5-video-player");
			if (player.classList.contains(cachedMode)) {
				document.querySelector("button.ytp-play-button").click();
				cachedMode = "";
			}
		}, 200);
	}
});