i cannot prove but i followed
@NiTroGen logic and it was fairly accurate back in the days when i tried out languages. working languages has
country codes while hiddens not. i don't know how accurate is this but in 1.0.6.16 ukrainian is hidden based on this. it listed in the file as
Ukrainian instead of
Ukrainian UK.
i guess that the only way to prove this if somebody install every old stuff step by step and change the phone's language.