Firefox add-on with keyword - panel

Gives you more control over Twitter and adds missing features and UI improvements

DevTools panel that displays technical details about media elements and webrtc on the current page; intended primarily for web developers to understand media playback issues on their sites, and for users to provide more informative bug reports.

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. :)

Gives you more control over YouTube by adding missing options and UI improvements

an easy way to check your Pinterest while you browse.

Easy access to Google Scholar right from Firefox's toolbar.

Swiftly access your search engines in a popup panel when you select text in a webpage. Context menu also included!

An extension that puts the browser history in the sidebar, sorted by date and domain.

An easy-to-use and lite App for YouTube.

Effortlessly open any website in your web browser's sidebar – streamline your workflow instantly!

Vertical tabs tree and bookmarks in sidebar with advanced containers configuration, grouping and many other features.

Allows you to hide contacts side panel on Whatsapp Web at will.

easy access to Gmail via toolbar-panel UI, plus, get badge notifications

An extension necessary for carrying out Netpanel study.

Displays a sidebar that allows you to view the mobile version of your web pages. Muestra una barra lateral que le permite ver la versión para móviles de sus páginas web.

Find admin panels by testing URLs with subdirectory extensions (only for pen-testing)

Block the right-side LinkedIn News Panel to focus more on what's important: your network.

itachi uchiha from naruto

Provides a bookmarks subpanel for Tree Style Tab's sidebar.

check your Instagram while you browse, plus, get badge notifications for new posts.

Zoom web pages (either per-site or per-tab) using full-page zoom, text-only zoom and minimum font size. Fit-to-width zooming can be applied to pages automatically. Fit-to-window scaling can be applied to small images.

An easy-to-use tab reloader with custom reloading time settings for individual tabs

Firefox Language Pack for 日本語 (ja) – Japanese

An Animation Throwdown tool to help you win

Edit the contents of a web page prior to printing or saving. Elements in the web page can be edited, formatted, hidden or deleted. Unwanted content, such as adverts and sidebars, can easily be removed.