Mastodon Thread Reader

A Firefox browser extension that renders any Mastodon thread as a clean, single readable page.

Features

• Auto-detects Mastodon post URLs on the active tab
• Fetches the full thread via the Mastodon API (ancestors + author's own replies)
• Displays posts in chronological order with avatars, timestamps, and inline images
• Image lightbox on click
• Dark mode support (respects prefers-color-scheme)
• Works on any Mastodon instance — no login or API key required

Installation

1. Clone or download this repository
2. Open Firefox and go to about:debugging
3. Click This Firefox → Load Temporary Add-on
4. Select the manifest.json file

For a permanent install, the extension would need to be signed via addons.mozilla.org.

Usage

1. Navigate to any Mastodon post (e.g. https://mastodon.social/@user/123456789)
2. Click the extension icon — the URL is pre-filled automatically
3. Click Open as readable thread — the thread opens in a new tab
4. You can also paste any Mastodon post URL manually in the reader page

How it works

The extension calls the public Mastodon REST API:

• GET /api/v1/statuses/:id — fetch the root post
• GET /api/v1/statuses/:id/context — fetch ancestors and descendants

Descendants are filtered to only include posts from the original author, so replies from others are excluded.

Project structure

manifest.json   Extension manifest (Manifest V2, Firefox)
popup.html/js   Browser action popup
reader.html/js  Full-page thread reader
icons/          SVG icons (48px, 96px)

Permissions

Only activeTab — used to read the current tab's URL for auto-detection.