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

RECOMMENDED

automaticDark - Time-Based Theme Changer

Make Firefox change colors based on time of day.
Get the extension

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.

    205,693 users

  • OneTab

    OneTab

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

    164,703 users

  • Simple Tab Groups

    Simple Tab Groups

    Create, modify, and quickly change tab groups

    97,192 users

  • Tab Session Manager

    Tab Session Manager

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

    139,298 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.

    376,406 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.

    393,511 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.

    106,428 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.

    43,892 users

“chat” tagged extensions
  • BetterTTV

    BetterTTV

    Enhances Twitch and YouTube with new features, emotes, and more.

    480,671 users

  • FrankerFaceZ

    FrankerFaceZ

    The Twitch Enhancement Suite - Get custom emotes and tons of new features you'll never want to go without.

    91,201 users

  • Netflix Party is now Teleparty

    Netflix Party is now Teleparty

    Watch Netflix, Youtube, Disney Plus, Hulu, HBO, and Amazon Prime Video in sync with friends

    65,023 users

  • Watch2Gether

    Watch2Gether

    With Watch2Gether you can watch videos together with your friends. Enhance your Watch2Gether experience with our official browser extension.

    55,128 users