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Search by Image

See an interesting picture on the web and want to learn more about it? Try this image search tool.
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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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Essential add-ons
Essential add-ons
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Reddit extensions
Reddit extensions
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Top rated themes
Tab managers
  • Tree Style Tab

    Tree Style Tab

    Show tabs like a tree.

    200,939 users

  • OneTab

    OneTab

    OneTab - Too many tabs? Convert tabs to a list and reduce browser memory

    163,733 users

  • Tabliss - New Tab

    Tabliss - New Tab

    A beautiful New Tab page with many customisable backgrounds and widgets that does not require any permissions.

    77,816 users

  • Tab Session Manager

    Tab Session Manager

    Save and restore the state of windows and tabs. It also supports automatic saving and cloud sync.

    140,122 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.

    385,236 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.

    394,529 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.

    105,920 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.

    40,318 users

“youtube” tagged extensions
  • Video DownloadHelper

    Video DownloadHelper

    Download videos from the web. Easy, smart, no tracking.

    1,823,501 users

  • Ghostery – Privacy Ad Blocker

    Ghostery – Privacy Ad Blocker

    The best privacy tool and ad blocker extension for Firefox. Stop trackers, speed up websites and block ads everywhere including YouTube and Facebook.

    1,018,057 users

  • Return YouTube Dislike

    Return YouTube Dislike

    Returns ability to see dislike statistics on youtube

    886,752 users

  • Enhancer for YouTube™

    Enhancer for YouTube™

    Take control of YouTube and boost your user experience!

    653,369 users