YouTube.com seek buttons (Mobile / Desktop)

Adds +-30sec +-1min +-5min buttons below the video. Works on mobile, tablet (m.youtube.com) and on desktop.

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

Bạn sẽ cần cài đặt một tiện ích mở rộng như Tampermonkey hoặc Violentmonkey để cài đặt kịch bản này.

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.

(Tôi đã có Trình quản lý tập lệnh người dùng, hãy cài đặt nó!)

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.com seek buttons (Mobile / Desktop)
// @namespace    m-youtube-com-seek-buttons
// @version      1.6
// @description  Adds +-30sec +-1min +-5min buttons below the video. Works on mobile, tablet (m.youtube.com) and on desktop.
// @author       hlorand.hu
// @match        https://m.youtube.com/*
// @match        https://youtube.com/*
// @match        https://*.youtube.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=tampermonkey.net
// @grant        none
// @license      https://creativecommons.org/licenses/by-nc-sa/4.0/
// ==/UserScript==

// Screenshot: https://ibb.co/72YKQPn
 
(function() {
    //'use strict';
 
    function addbuttons(){
        document.getElementById("seekbuttons").innerText = "";
 
        const times = ["+300s", "+60s", "+30s", "-30s", "-60s", "-300s"];
 
        times.forEach((time)=>{
            let button = document.createElement('button');
            button.textContent = time;
 
            button.style.margin = "4px";
            button.style.padding = "4px";
            button.style.backgroundColor = "purple";
            button.style.position = "relative";
 
            button.onclick = function() {
                let video = document.querySelector("video");
 
                if(video && video.readyState >= 2) {
                    video.currentTime += parseInt(this.textContent.replace("s",""));
                }
            };
 
            let target = document.getElementById("seekbuttons");
            target.insertBefore(button, target.firstChild);
 
        }); // end times foreach
 
    } // end addbuttons
 
    // Periodically check if the buttons are visible 
    // (sometimes YouTube redraws its interface).
    setInterval(()=>{
        // Creating a div that will contain buttons.
        if( document.getElementById("seekbuttons") == undefined ){
            
            // placement of buttons on desktop
            let parent = document.getElementById('above-the-fold');

            // placement of buttons on tablet
            if( !parent ){
                parent = document.querySelector('.watch-below-the-player');
            }

            // placement of buttons on mobile
            if( !parent ){
                parent = document.querySelector('.related-chips-slot-wrapper');
            }

            let wrapper = document.createElement('div');
            wrapper.setAttribute("id","seekbuttons");
            parent.insertBefore(wrapper, parent.firstChild);
            addbuttons();
        }

        // Sometimes the buttons are not added, so I check and add them if necessary.
        if( document.getElementById("seekbuttons").textContent.trim() === '' ){
            addbuttons();
        }

    }, 1000);

})();