Mozilla Firefox is a popular web browser that is used by millions of people around the world. It has a number of features that make it an excellent choice for online browsing. One of the most popular add-ons for Mozilla Firefox is Extensions. Extensions are add-ons that allow you to add new features or changes to Mozilla Firefox. They can be installed from the Mozilla Firefox Add-on Store, or from a third-party website. When you install an extension, Mozilla Firefox will ask you to choose a name for the extension and to provide some basic information about it, such as its author and version number. After you have chosen a name and provided some additional information, Mozilla Firefox will install the extension and start using it. You can use any language to create extensions for Mozilla Firefox, but English is the default language used by extensions on the store. If you want your extension to work in another language, you must set up a translation project and submit it to the store in that language. If you have any questions about installing extensions or using them in Mozilla Firefox, please feel free to contact us at support@mozilla.org or visit our Extension Support page on our website.


An extension is an add-on to the browser that adds functionality. Extensions can be tools that extend the abilities of the Mozilla Firefox browser. Other types of extensions add integration with services, making them more convenient to use in the browser.

Firefox classifies extensions as a type of “Add-On” along with Themes. Unlike with some other browsers, such as Google Chrome, Firefox not only supports add-ons on your desktop, but also in the Android app.

Mozilla maintains a repository of all the add-ons. Not all of the extensions you can use on the desktop are available for Android. We’ll show you how to find and install them on both platforms.

Install Extensions in Firefox for Desktop

Open Firefox on your Windows 10, Mac, or Linux PC. From there, click the hamburger menu icon in the top-right corner of the window.

Next, select “Add-Ons” from the drop-down menu.

This is where any extensions or themes you have installed can be found. To download extensions, click “Find More Add-Ons” at the bottom of the page.

You’re now on Mozilla’s storefront for add-ons. Click the “Extensions” tab to browse, or use the search box at the top of the screen.

Once you find an extension that you like, select it to see more information about it. Click “Add to Firefox” to install the extension.

A pop-up will appear with information about the permissions required for the extension. Click “Add” to continue the installation.

Lastly, a message will show you where the extension lives. Click “Okay, Got It” to finish up.

The Firefox add-on is now installed and running on your computer.

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Install Extensions on Firefox for Android

Firefox for Android doesn’t have as many extensions as the desktop app, but it still has more than most mobile browsers.

First, open Firefox on your Android phone or tablet and tap the three-dot menu icon in the bottom bar.

Next, select “Add-Ons” from the menu.

This is the list of available extensions for the Android app. Tap the extension name to see more information, then tap “+” to install the add-on.

A pop-up message will explain the required permissions. Tap “Add” to continue installing.

Lastly, a message will show you where the extension can be accessed. Tap “Okay, Got It” to finish up.

Firefox was one of the first browsers to support extensions, and it still boasts a great selection. It’s great that some of the extensions are available on Android, too. Now that you know how to install them, go forth and make the browser even better.

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