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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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Privacy & Security extensions
Privacy & Security extensions
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Tab managers
Tab managers
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The joy of creating themes
The joy of creating themes
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Extension starter pack
  • Enhancer for YouTube™

    Enhancer for YouTube™

    Take control of YouTube and boost your user experience!

    618,500 users

  • Privacy Badger

    Privacy Badger

    Automatically learns to block invisible trackers.

    1,389,645 users

  • Grammar and Spell Checker - LanguageTool

    Grammar and Spell Checker - LanguageTool

    With this extension you can check text with the free style and grammar checker LanguageTool. It finds many errors that a simple spell checker cannot detect, like mixing up there/their, a/an, or repeating a word.

    377,660 users

  • Search by Image

    Search by Image

    A powerful reverse image search tool, with support for various search engines, such as Google, Bing, Yandex, Baidu and TinEye.

    365,814 users

Creativity extensions
  • Grammar and Spell Checker - LanguageTool

    Grammar and Spell Checker - LanguageTool

    With this extension you can check text with the free style and grammar checker LanguageTool. It finds many errors that a simple spell checker cannot detect, like mixing up there/their, a/an, or repeating a word.

    377,660 users

  • Search by Image

    Search by Image

    A powerful reverse image search tool, with support for various search engines, such as Google, Bing, Yandex, Baidu and TinEye.

    365,814 users

  • Dark Background and Light Text

    Dark Background and Light Text

    Make every web page (or just the pages you want) display light text on dark backgrounds. All color variations are fully customizable.

    32,846 users

  • LeechBlock NG

    LeechBlock NG

    LeechBlock NG is a simple productivity tool designed to block those time-wasting sites that can suck the life out of your working day. All you need to do is specify which sites to block and when to block them.

    78,063 users

Steam enhancers
  • SteamDB

    SteamDB

    Adds SteamDB links and new features on the Steam store and community. View lowest game prices and stats.

    56,658 users

  • Augmented Steam

    Augmented Steam

    Augments your Steam Experience

    57,379 users

  • Steam URL Opener

    Steam URL Opener

    Allows you to open URLs inside Steam Client to save the hassle of logging in normal browser (with a single click on a button).

    4,619 users

  • ProtonDB for Steam

    ProtonDB for Steam

    Shows ratings from protondb.com on Steam

    3,033 users

“social media” tagged extensions
  • Return YouTube Dislike

    Return YouTube Dislike

    Returns ability to see dislike statistics on youtube

    752,511 users

  • Enhancer for YouTube™

    Enhancer for YouTube™

    Take control of YouTube and boost your user experience!

    618,500 users

  • Easy Youtube Video Downloader Express

    Easy Youtube Video Downloader Express

    A simple extension for superfast and easy YouTube downloads in FLV, 3GP, MP3, MP4, 720p, and 1080p formats.

    551,473 users

  • 'Improve YouTube!'  🎧 (For YouTube & Video)

    'Improve YouTube!' 🎧 (For YouTube & Video)

    Youtube Extension. Powerful but lightweight. Enrich your Youtube & content selection. Make YouTube tidy&smart! Layout Filters Shortcuts Adblocker Playlist

    59,497 users