- Click on the Install Now link on the downloads section
- Click in the Edit Options button shown below

- In the window that will open click on the Allow button
- Click again on the Install Now link on downloads section
- Wait 3 seconds and click on the Install Now button

- Wat for the download to finish and restart Firefox.
Customize the size of the toolbar icons:
- In the addres field of Firefox type about:config;
- The Firefox preferences will appear;
- Find and click twice in the option "otb.opt.iconsize";
- Put the value 1 for big icons;
- Put the value 2 for small icons (default).
