Take tabs from parent windows and arrange them in layouts of tiled sub-windows, using the toolbar button, context menu or keyboard shortcuts. Makes it easy to browse, compare or monitor multiple pages. Synchronize scroll. Save and re-open layouts.

Custom color schemes for all websites: night mode, dark themes, blue light filter, screen shader, high contrast, grayscale, etc.

One click to close any overlay popup on any website.

Use keyboard shortcut Cmd+Shift+X (Mac OS X) or Ctrl+Shift+X (Windows / Linux).

Customizes the new tab page. Add more tiles. Have a background image. Set new tile images and titles. See recently closed tabs. And more...

The cross-browser extension that manipulates video aspect ratio to fit your entire screen.
Netflix | Prime Video | Disney+ | Hulu | ESPN | + Many others... 🚀

Sets "Always on Top" style for your Firefox window

Auto Fullscreen for Firefox Quantum

Theme Font & Size Changer lets you change the global font size and font family used for the user interface in Firefox. Design your browser with your favorite font.

The Tab Rotator automatically switches between the open tabs of a browser window after a certain amount of time.

Simplifies the GitHub interface and adds many useful features.

Open and save Instagram photos, videos, stories and reels.

Extension that sets a custom default zoom for all pages in Firefox.
You can set a general zoom for all pages or custom rules depending on the site.

Non linked URL open with double click.
and
Google translate.

By blocking annoying ads and nosy trackers, Adaware AdBlock nearly doubles your browsing speed! And with the most robust antivirus-level cloud-scanning technology of any ad blocker on the market, you’ll be safe from the latest cyber-threats.

Fun custom cursors for Firefox. Use a large collection of free cursors or upload your own.

A keyboard shortcut tool for keyboard-based page navigation and browser tab operations with an advanced omnibar and global shortcuts

Find yourself spending too much time on Facebook? Eradicate distractions by replacing your entire news feed with an inspiring quote

Control your browser faster and easier with gestures using mouse movement.

Temporary disposable email address. Protect your email from spam, bots and phishing with Temp-Mail.

Automatically change Firefox's theme based on the time.

Crowdsourcing titles and thumbnails to be descriptive and not sensational

Zoom in or out on web content using the zoom button and mouse scroll wheel for more comfortable reading. That to each percent value. It helps you to zoom easily in and out a web page. Thanks to the slider and the zoom buttons.

This add-on likely is only useful for users who speak German or visit German language websites - it will remove so called "Binnen-Is" on webpages.

Replaces thumbnails and modifies titles of videos on youtube.com and m.youtube.com

Permanently hides the Ads panel on the right side of New Yahoo! Mail, the 'Sponsored' email at the Top, and ads on the Left to give you a full-width Premium email experience for free! The other option, of course is to pay $50 a year to Yahoo! Inc. :)

Allows you to hide almost anything in any page via context menu

Change the appearance of the web instantly

Set your search engine to Bing.com to check out the latest news, entertainment and sports each day and turn your searching into doing with Bing.

Reopens the last closed tab.

Dark mode for Google Docs!