To use these add-ons, you'll need to download Firefox.

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Sidebery

Tabs and bookmarks neatly organized in a Firefox side view.
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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!

    663,935 users

  • Privacy Badger

    Privacy Badger

    Automatically learns to block invisible trackers.

    1,459,122 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.

    397,497 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.

    374,430 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.

    397,497 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.

    374,430 users

  • Dictionary Anywhere

    Dictionary Anywhere

    View definitions easily as you browse the web. Double-click any word to view its definition in a small pop-up bubble. It also supports Spanish, German, French language alongside English. Enjoy Reading Uninterrupted!!!.

    44,358 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.

    80,405 users

Steam enhancers
  • SteamDB

    SteamDB

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

    58,783 users

  • Augmented Steam

    Augmented Steam

    Augments your Steam Experience

    58,561 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).

    5,001 users

  • ProtonDB for Steam

    ProtonDB for Steam

    Shows ratings from protondb.com on Steam

    3,216 users

“mp3” tagged extensions
  • 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.

    555,899 users

  • 600% Sound Volume

    600% Sound Volume

    Up to 600% volume boost

    170,146 users

  • Global Speed

    Global Speed

    Set a default speed for video and audio.

    68,319 users

  • YouTube mp3

    YouTube mp3

    The YouTube-mp3 Add-on generates a "MP3" button on YouTube. Convert YouTube to mp3 and download the file to your device.

    36,081 users