Add-ons for Firefox (en-US)

RECOMMENDED

Simple Translate

Instantly translate any selected text on web pages.

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Extensions are like apps for Firefox.

They add features to Firefox to make browsing faster, safer, or just plain fun.

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Productivity tools

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YouTube customization

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Privacy & Security extensions

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Recommended extensions

Privacy Badger
Automatically learns to block invisible trackers.
Rated 4.8 out of 5
EFF Technologists
1,873,379 users
Measure-it
Draw a ruler across any webpage to check the width, height, or alignment of page elements in pixels.
Rated 4.4 out of 5
Trishul
26,604 users
Auto Tab Discard
Increase browser speed and reduce memory load and when you have numerous open tabs.
Rated 4.5 out of 5
tlintspr
73,576 users
Stylus
Redesign your favorite websites with Stylus, an actively developed and community driven userstyles manager. Easily install custom themes from popular online repositories, or create, edit, and manage your own personalized CSS stylesheets.
Rated 4.7 out of 5
Stylus Team
129,647 users

Top rated themes

Kirby9
Rated 5 out of 5
＼(^o^)／
8,888 users
Praise the sun (animated)
Rated 4.9 out of 5
anon
15,507 users
Spirited Away (Animated)
Rated 4.9 out of 5
Max
21,759 users

Tab managers

Tabby - Window & Tab Manager
Tabby helps you manage a lot of windows and tabs easily; it can help you open, close, move, pin, and do many other things on tabs and windows quickly. With Tabby, you can even save all you windows and tabs for later with just one click!
Rated 4.3 out of 5
BillK
17,172 users
Tree Style Tab
Show tabs like a tree.
Rated 4.5 out of 5
Piro (piro_or)
221,679 users
Simple Tab Groups
Create, modify, and quickly change tab groups
Rated 4 out of 5
Drive4ik
102,329 users
OneTab
OneTab - Too many tabs? Convert tabs to a list and reduce browser memory
Rated 4.2 out of 5
OneTab Team
171,796 users

Popular extensions

uBlock Origin
Finally, an efficient wide-spectrum content blocker. Easy on CPU and memory.
Rated 4.8 out of 5
Raymond Hill
9,570,528 users
Video DownloadHelper
Download videos from the web. Easy, smart, no tracking.
Rated 4.3 out of 5
mig
1,940,486 users
Privacy Badger
Automatically learns to block invisible trackers.
Rated 4.8 out of 5
EFF Technologists
1,873,379 users
AdGuard AdBlocker
Unmatched adblock extension against advertising and pop-ups. Blocks ads on Facebook, Youtube and all other websites.
Rated 4.7 out of 5
Adguard Software Ltd
1,402,167 users

Recommended themes

Everforest Dark Medium Theme
Rated 5 out of 5
Bullfinch
481 users
Squartoranges
Rated 4.8 out of 5
MajinPat
42 users
Dark Metall 1717
Rated 4.4 out of 5
Albert Baum
10,928 users

Twitch extensions

BetterTTV
Enhances Twitch and YouTube with new features, emotes, and more.
Rated 4.6 out of 5
NightDev
483,597 users
Alternate Player for Twitch.tv
Alternate player of live broadcasts for Twitch.tv website.
Rated 4.3 out of 5
Alexander Choporov (CoolCmd)
35,182 users
Twitch Chat pronouns
Add Pronouns to Twitch Chat
Rated 3.4 out of 5
Alejo Pereyra
15,971 users
Unwanted Twitch
Hide unwanted streams, games, categories, channels and tags on: twitch.tv
Rated 4.2 out of 5
kwaschny.net
5,765 users

“dark mode” tagged extensions

Dark Reader
Dark mode for every website. Take care of your eyes, use dark theme for night and daily browsing.
Rated 4.5 out of 5
Dark Reader Ltd
1,295,436 users
Enhancer for YouTube™
Take control of YouTube and boost your user experience!
Rated 4.7 out of 5
Maxime RF
672,221 users
Block Site
A customizable, password-protected website blocker and redirector.
Rated 3.9 out of 5
Ray
76,337 users
'Improve YouTube!' 🎧 (For YouTube & Video)
Youtube Extension. Powerful but lightweight. Enrich your Youtube & content selection. Make YouTube tidy&smart! Layout Filters Shortcuts Adblocker Playlist
Rated 4.4 out of 5
code-for-charity
56,829 users