auto_click_related.js

// ==UserScript==
// @name         Auto click "Related" sidebar button
// @namespace    http://tampermonkey.net/
// @version      0.3
// @description  Auto click "Related" sidebar button
// @author       Zack H
// @match        https://www.youtube.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=youtube.com
// @grant        none
// @homepage     https://gist.github.com/zphixon/fdedb0db45feb4f8c8dd4cf53b6d89a1
// ==/UserScript==

(function() {
    'use strict';

    const chipSelector = 'yt-chip-cloud-chip-renderer';
    const autoSelectIntervalMs = 1000;

    // Unfortunate state-tracking variables
    let shouldAutoClick = true;
    let wasAutoClick = true;
    let chipsWithClickListeners = [];
    let prevLocation = window.location.href;

    // Tampermonkey's builtin eslint complains if I reference the variables directly, so put
    // them behind doubly-unfortunate getters/setters. hmmmm
    let getWasAutoClick = () => wasAutoClick;
    let setWasAutoClick = (newValue, why) => {
        wasAutoClick = newValue;
    };
    let setShouldAutoClick = (newValue, why) => {
        shouldAutoClick = newValue;
    };

    let doAutoSelectRelated = () => {
        // Only look for chips on the watch page - We don't use @match for this, since
        // navigating to the watch page from the subscriptions page doesn't seem to reliably
        // re-run this script. YouTube must be doing something weird.
        if (!window.location.href.includes('youtube.com/watch')) {
            return;
        }

        // We also haven't reliably re-run this script when clicking on a video from the
        // sidebar, so re-enable auto clicking if we think we navigated somewhere new.
        if (window.location.href != prevLocation) {
            setShouldAutoClick(true);
        }
        prevLocation = window.location.href;

        // Find the chip we want to click on
        let chipToClick;
        for (let chip of document.querySelectorAll(chipSelector)) {
            if (chip.textContent.trim() == 'Related') {
                chipToClick = chip;
            } else if (chip.textContent.trim().startsWith('From ') && chipToClick == undefined) {
                // Prefer "Related", but accept "From ChannelName" if there is no "Related"
                chipToClick = chip;
            }

            if (!chipsWithClickListeners.includes(chip)) {
                chipsWithClickListeners.push(chip);
                chip.addEventListener('click', () => {
                    // If the user clicked on a chip, stop auto-clicking.
                    if (!getWasAutoClick()) {
                        setShouldAutoClick(false);
                    }

                    // We no longer care if this was an auto-click.
                    setWasAutoClick(false);
                });
            }
        }

        if (chipToClick && shouldAutoClick && !chipToClick.selected) {
            // This was an auto-click. Don't stop auto-clicking yet - the chips seem to
            // disappear and reappear on page load sometimes, which re-selects All. We
            // may need to click Related again.
            setWasAutoClick(true);
            chipToClick.click();
        }
    };

    setInterval(doAutoSelectRelated, autoSelectIntervalMs);
})();