tell me about it! literally the ONE thing keeping me from FF at the moment. vertical tabs are too vital to my workflow at this point to sacrifice.

I don't know exactly how to do it, I know you can because when I was in the firefoxcss subreddit there were many posts on how people came up with their own solutions for vertical tabs.

I wanted vertical tabs to save on screenspace, for some reason the default firefox has the biggest top bar of all browsers and it is horrible, this is the userChrome.css that I use, it does what I wanted but it is not vertical tabs:

https://imgur.com/h39dsHL.png

https://pastebin.com/r54QRbKx

It is also keyboard centric, I also had to install an extension because firefox (and this only happens on linux) uses alt+number to switch between tabs instead of control+number.