I wish they'd stop messing with things that don't need "fixing"!
Version 75 certainly made a mess of the address bar on my PC! Not sure if that's because I use the Custom CSS fixes from https://github.com/Aris-t2/CustomCSSforFx to put Firefox back the way I prefer it or something else.
If you are having the same issues or just prefer the way it used to work then try this which disables the new address bar settings:
Put about:config into the address bar and press return to get at the internal Firefox settings (click past the warning). Then search for the following four settings and double click each one to change it from "true" to "false":
You may need to close and restart FF in order to make it all work.
(Disclosure: I found this on Ars Technica where lots of people were complaining about the "new address bar goodness" - when will they learn - sigh!)