In #Waterfox, at least in #Gnome, you can navigate tabs with SHIFT+ALT+ARROW.
I've been yearning for that for like two years.
In Firefox, it's CTRL+PGUP/PGDOWN, and I find that super awkward. That's a preference thing. Not saying it's bad. But it doesn't work for me.
#FOSS #FLOSS #OpenSource #Linux #Debian