yt.ad.forward-backward.user.js

// ==UserScript==
// @name         Youtube A+D forward back speed
// @namespace    http://tampermonkey.net/
// @license      Unlicense
// @version      2024-03-05
// @description  Youtube A+D forward back speed
// @author       dung691
// @match        https://www.youtube.com/*
// @grant        none
// @updateURL    https://gist.githubusercontent.com/dung691/d780a6e6d0e316c3d693f32cc94d8c4d/raw/yt.ad.forward-backward.user.js
// @downloadURL  https://gist.githubusercontent.com/dung691/d780a6e6d0e316c3d693f32cc94d8c4d/raw/yt.ad.forward-backward.user.js
// ==/UserScript==

(function() {
    'use strict';

    document.addEventListener('keydown', function (event) {
        if (!isWatchPage() && !isShortsPage()) return;
        var video = document.querySelector('video.html5-main-video');
        if (!video) return;
        if (event.code === 'KeyA') {
            video.currentTime -= 5;//Math.floor(videoElement.duration * 0.05);
        } else if (event.code === 'KeyD') {
            video.currentTime += 5;//Math.floor(videoElement.duration * 0.05);
        }
    });

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

    function isShortsPage() {
        return /^\/shorts/.test(location.pathname);
    }
})();