From OTRS - https://ticket.wikimedia.org/otrs/index.pl?Action=AgentTicketZoom;TicketID=11302381

This is not a real bug, but only a limitation of the app. I use Wikipedia in half a dozen languages, according to my needs. However, in the screen in which I can choose among those Wikipedias, only the first three languages appear, though a lot of space is available. This I find puzzling and rather aggravating — though in general, I like the app.

In the picture below I have 6 languages set, but only 3 appear on the search page