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

RECOMMENDED

Tab Stash

Save batches of tabs as convenient bookmarks.
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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.

    203,249 users

  • OneTab

    OneTab

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

    163,246 users

  • Simple Tab Groups

    Simple Tab Groups

    Create, modify, and quickly change tab groups

    95,916 users

  • Tab Session Manager

    Tab Session Manager

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

    137,925 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.

    370,755 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.

    391,028 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.

    105,369 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.

    42,691 users

“dark mode” tagged extensions
  • Dark Reader

    Dark Reader

    Dark mode for every website. Take care of your eyes, use dark theme for night and daily browsing.

    1,224,534 users

  • Enhancer for YouTube™

    Enhancer for YouTube™

    Take control of YouTube and boost your user experience!

    646,705 users

  • Block Site

    Block Site

    A customizable, password-protected website blocker and redirector.

    72,442 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

    63,061 users