One nice thing about Firefox is that you can theme it with some CSS. You can make minor modifications or go completely custom. Not only can you change colors, but you can move things around and create custom browser experiences.
Here are some pretty awesome looking Firefox themes that you can install today.
Do keep in mind that Firefox does have some differences on different operating systems so not everything will work perfectly if the author didn’t test on your OS. Additionally, Firefox updates can break themes as the browser evolves. If something isn’t right, you’ll either wait for an update or make the fixes yourself if you know how to code.
Moonlight

Firefox GNOME theme

elementary OS

Firefox Safari Style

FF Midnight

MaterialFox (Mimic Chrome)

Firefox etals

Sweet Theme

Aqua (Mimic Safari)

Slickfox

Firefox Transparent One-Line/Two-Line

Safari-esque Light & Dark

Firefox-Mod

Slimbar

Simplify Silver Peach for Firefox

Moz-Mac

There’s a lot more out there, but they’re hard to find. I typically find them by searching GitHub or following FirefoxCSS on Reddit. FirefoxCSS is also a great place to start learning how to create your own custom Firefox themes.
Which themes are your favorite? Or do you have any to share? Let me know in the comments below or @TwisterMc.
There are some beautiful themes for Firefox here, but I don’t know how to install a GitHub theme. And I bet I’m not the only one.
Yep. That’s a hurdle. Do the instructions here help? https://github.com/TwisterMc/moz-mac