[Koha] opaclanguages

Hi everybody I have installed italian (it-IT) package in my Koha 20.05 on Ubuntu 20 but in the preference tab i18n_l10n I have both languages (it-IT and en) in language field while in the opaclanguages there is only the English (en) check box. some of you have an Idea on how those two checlbox lists works? thanks a lot tommaso