There are lots of great add-ons that you can install to add features to Firefox. This article explains how to find, install and manage add-ons in Firefox for Android.
You can access the Android add-ons from inside Firefox for Android:
Updating your add-ons: When you update Firefox for Android, it will automatically update your add-ons to compatible versions if they're available.
Temporary disable or permanently uninstall an add-on: