You can easily extend the features of the Firefox web browser with extensions/add-ons and themes. In the FAQ you will learn how to install a browser extension on the mobile version of Firefox.
NB: these add-ons have been optimized for use on a mobile device.
First download and install Firefox from the Play Store
Tap on the Menu button > Tools.
Tap on Add-Ons
Tap on Browse all Firefox Add-ons
You will be redirected to the add-ons/themes gallery.
Tap to select the add-on or theme you want to install.
Tap on Add to Firefox > Install.
You can view your installed add-ons by going to: Menu > Tools > Add-Ons > Your Add-Ons
Firefox for Android - How to install add-ons and themes
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