Mozilla Firefox is a free web browser with full of useful features, more interesting, there are many necessary add-ons to help you surf the web more effectively than ever before!
So, do you know how to install those add-ons, or extensions? Please, Download.com.vn, learn the steps to install the extension on Firefox!
Step 1: Open up Mozilla Firefox, click on the word Firefox (top left corner), select Add-ons (or use the shortcut Ctrl + Shift + A ).

Step 2: The Manage add-on window appears, type the name of the add-on to search in the search box, the corresponding add-on list will appear right below, find the correct add-on you need, click Install.

Step 3: Firefox will automatically download and install the add-on for you, after the installation is complete, click Restart now to restart Firefox.

Step 4: Then go to Firefor / Utilities / Extensions to see if that add-on has been installed.

Now you can use this utility, here you can also Disable, Delete or select some other options for this utility.

In addition, you can go to Download.com.vn to find some add-ons you need here .
Good luck!