After you’ve used Firefox for a while, you may have the desire to tinker around with the userChrome.css file and tweak it a bit for your likes or dislikes. Unfortunately, finding the userChrome.css is a bit confusing for people - particularly when the file doesn’t actually exist. This is something that was a bit confusing to me in the past, so I imagine that at least one other person out there has had a problem figuring out how to do this also.

For people who, like myself, are trying to get good at Linux by using Ubuntu, sorting through things at the command line is a tad intimidating, but I’m going to walk you through it and show you that it’s not so scary. In fact, I’m actually using my command line a lot more these days in Linux.

I’m going to give an example using one of the simple things you can do with the userChrome.css — we’ll change the sidebar from opening on the left to opening on the right. I’ll show you both ways in Ubuntu, the terminal way, and the file manager way.