Install a theme
Tired of the grey default theme? Perfect! Here's how to give your browser a fresh new look! 1) Open Firefox and go on addons.mozilla.org .2) In the categories on the left, click on Themes.
3) On the top of the page, you have the recommended themes, but if you want to see more, scroll down to see the different categories of themes. I recommend modern, but you can choose whatever inspires you.
4) The themes are sorted by alphabetical order, which isn't great. Sort them by dowloads (most popular first) or date (most recent first), instead.
5) Click on one theme that you like, then click on the green button that says Add to Firefox.
6) A window will pop up, asking you if you want to install the theme. Click on Install Now.
7) If the theme looks weird, close Firefox, then open Firefox.
Firefox now looks beautiful and full of life, congratulations!
Note: To go back to the default theme, click on Tools, then on Add-ons in the Firefox menu. Select the default theme, then click Use theme.