@dzu I've just installed it. I think I continue to use it tty only. Emacs has a web-browser which I use from time to time.
On my normal setup I use Guix with Ratpoison wm for Xorg, which is lightweight, but as you noticed software like Firefox is not lightweight and many GUI apps are like that. Would be nice to use just 10-15 years old firefox, but packaging old software in GNU Linux world is a bit broken and can be incompatible with newer libraries and compilers in many ways.