Firefox Extension GitHub Repositories (2026) · Open Source Tools

StackPrism is a browser extension for detecting website technology stacks.

A browser extension for easy on-device translation with a local LLM (PLaMo). Private, free, no server needed.

Stylus - Userstyles Manager

An open-source desktop app for macOS, Windows and browsers to monitor the performance and health of your Starlink.

Convert any web page to clean, readable Markdown with just one click.

:cloud: Sync your bookmarks privately across browsers and devices

QOwnNotes is a plain-text file notepad and todo-list manager with Markdown support and Nextcloud / ownCloud integration.

The cross-browser extension framework.

A browser extension that redirects popular sites to alternative privacy friendly frontends

scanner detecting the use of JavaScript libraries with known vulnerabilities. Can also generate an SBOM of the libraries it finds.

m3u8 file downloader library and chrome & firefox extensions/add-on's

Turn Off the Lights Browser extension for Google Chrome, Firefox, Opera, Safari, Naver Whale, Yandex, Samsung Internet, and Microsoft Edge.

Read one post and leave. Chrome and Firefox extension that opens X and Bluesky post links in a popup, not the full site. No account, no cookies sent to either.

Turn any website into a native-like Android app

Web extension that adds keyboard shortcuts to Google, YouTube, Github, Amazon, and others (Chrome/Firefox/Edge/Safari)

An awesome browser extension that reads aloud webpage content with one click

Chrome extension to return youtube dislikes

Integrating ChatGPT into your browser deeply, everything you need is here

Reddit Enhancement Suite

Don't waste your time with compliance. FastForward automatically skips annoying link shorteners.