I would use LibreWolf IF it had cloud sync, since that’s a feature I actively use with regular Firefox.
edit: I tried LibreWolf and Waterfox. I copied over my Firefox profile to LibreWolf and Waterfox. LibreWolf works with all of my addons and even Firefox Sync and everything else, I had to disable “Enable ResistFingerprinting” to fix login on a couple sites and also had to prevent it from deleting cookies and site data when LibreWolf is closed but now it works perfectly for me, same as Firefox works perfectly for me. Waterfox has tons of issues with my addons like with uMatrix enabled it straight up just refuses to work, also loading all pages is slower, and one of my mail addons also has some weird corruption - Waterfox is unusable for me. I think LibreWolf is a great fit for me so I think I will most likely use that if I can be bothered, or maybe I will stick with Firefox, who knows, we’ll see I guess. Still though, LibreWolf seems great.