Reddit Comment Auto-Expander (Smooth)

Automatically and smoothly expands all collapsed comments on Reddit [except for permalink ones...] with enhanced performance

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

You will need to install an extension such as Tampermonkey to install this script.

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.

(I already have a user script manager, let me install it!)

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         Reddit Comment Auto-Expander (Smooth)
// @namespace    _pc
// @author       verydelight
// @version      1.08
// @license      MIT
// @compatible   Firefox Tampermonkey
// @description  Automatically and smoothly expands all collapsed comments on Reddit [except for permalink ones...] with enhanced performance
// @match        *://*.reddit.com/r/*/comments/*
// @grant        none
// @run-at       document-start
// ==/UserScript==
(function() {
	'use strict';
	const pre_load = 1200;
	const batch_size = 12;
    const DELAY_INTERVAL = 15; // Extracted for clarity

    // Global flags for pausing
    let isEditActive = false; // Pauses Observer and Expansion Checks
    let isClickingBatch = false; // NEW: Pauses all SafeClicks during batch execution

    // Inject CSS style to lock the editor from script clicks
    const style = document.createElement('style');
    style.id = 'reddit-editor-lock';
    style.textContent = `
      .userscript-editor-lock * {
        pointer-events: none !important;
      }
    `;
    (document.head || document.documentElement).appendChild(style);

	function safeClick(el) {
        // CRITICAL CHECK: Block clicks if a batch is currently executing (the timing issue)
        if (isClickingBatch) return;

        // Block clicks if the editor lock is on (the detection issue)
        if (isEditActive) return;

		if (!el || el.disabled || el.offsetParent === null) return;
		const event = new MouseEvent('click', { bubbles: true, cancelable: true });
		el.dispatchEvent(event);
	}

	function isInViewport(el) {
		const rect = el.getBoundingClientRect();
		return rect.top < window.innerHeight + pre_load && rect.bottom > -pre_load;
	}

	function expandVisible() {
        // AGGRESSIVE EDITOR DETECTION BLOCK
        const activeComposer = document.querySelector('shreddit-comment-composer, shreddit-post-composer, faceplate-modal');

        // PAUSE LOGIC: If an editor/modal is found, pause everything.
        if (activeComposer) {
            (activeComposer.closest('body') || activeComposer).classList.add('userscript-editor-lock');
            isEditActive = true;
            return;
        }

        // RESUME LOGIC: If no editor is found, resume.
        const lockedComposer = document.querySelector('.userscript-editor-lock');
        if (lockedComposer) {
            lockedComposer.classList.remove('userscript-editor-lock');
        }
        isEditActive = false;

        // ** EXACT ORIGINAL EXPANSION LOGIC **
		const batch = [];
		const editor = document.querySelector('[data-test-id="post-content"], [data-testid="comment"]');

		document.querySelectorAll('shreddit-comment button[aria-controls][aria-expanded="false"], shreddit-comment button[rpl]:not([aria-expanded="true"])')
		.forEach(btn => {
			if (btn.closest('aside')) return;
			if (editor && editor.contains(btn)) return;
			if (isInViewport(btn) && !btn.closest('shreddit-comment-action-row')) batch.push(btn);
		});

		document.querySelectorAll('faceplate-partial button')
		.forEach(btn => {
			if (btn.closest('aside')) return;
			if (editor && editor.contains(btn)) return;
			if (isInViewport(btn) && !btn.closest('shreddit-comment-action-row') && btn.offsetParent !== null) batch.push(btn);
		});

		document.querySelectorAll('shreddit-comment[collapsed]')
		.forEach(comment => {
			if (comment.closest('aside')) return;
			if (editor && editor.contains(comment)) return;
			if (!isInViewport(comment)) return;
			const btn = comment.querySelector('button[aria-controls]');
			if (btn && btn.getAttribute('aria-expanded') === 'false') batch.push(btn);
			else if (!btn) batch.push(comment);
		});

        // Only run if there's work to do
        if (batch.length === 0) return;

        // Set the global click lock on while batches are scheduled
        isClickingBatch = true;

		for (let i = 0; i < batch.length; i += batch_size) {
            // Calculate when the last timeout will execute
            const lastTimeoutTime = (batch.length - 1) * DELAY_INTERVAL;

			setTimeout(() => {
				batch.slice(i, i + batch_size).forEach(el => {
					safeClick(el);
					if (el.matches('shreddit-comment[collapsed]') && !el.querySelector('button[aria-controls]')) {
						el.removeAttribute('collapsed');
						el.querySelectorAll('[slot^="children"], [slot="next-reply"]').forEach(child => {
							child.hidden = false;
							child.style.display = '';
						});
					}
				});

                // Check if this is the very last batch to execute
                if (i + batch_size >= batch.length) {
                    // Schedule the unlock to happen after a small buffer
                    setTimeout(() => {
                        isClickingBatch = false;
                    }, DELAY_INTERVAL + 1); // Add a small buffer delay
                }

			}, i * DELAY_INTERVAL);
		}
	}

    // MUTATION OBSERVER PAUSE
	const observer = new MutationObserver(mutations => {
        if (isEditActive) return;

		mutations.forEach(m => {
			if (m.type === 'childList' && m.addedNodes.length > 0) {
				expandVisible();
			}
		});
	});

	function initObserver() {
		const container = document.querySelector('shreddit-comments') ||
		document.querySelector('[data-test-id="comments-page"], [data-testid="comments-page"]') ||
		document.querySelector('shreddit-comment')?.closest('main, #SHORTCUT_FOCUSABLE_DIV, body');
		if (!container) {
			setTimeout(initObserver, 250);
			return;
		}
		observer.observe(container, { childList: true, subtree: true });
		expandVisible();
	}

	initObserver();
	window.addEventListener('scroll', () => expandVisible());
    window.addEventListener('mousedown', expandVisible);
})();