In WikibaseRepo there are two types of content languages: term languages and monolingual text languages. In the frontend code, Termbox currently consumes the monolingual text languages when it should be using term languages. This only affects Termbox v2 (mobile).
**Technical Notes**:
In the PHP code, there is [`WikibaseContentLanguages::getContentLanguages`](https://github.com/wikimedia/Wikibase/blob/d487b458700cd7cb3d56c71123238c6426011096/lib/includes/WikibaseContentLanguages.php#L39) to get either term languages or monolingual text languages. In the frontend, there is a similarly named [`WikibaseContentLanguages`](https://github.com/wikimedia/Wikibase/blob/ad5ea7a1712766d9a0c39aad75beb091d9f99a29/repo/resources/wikibase.WikibaseContentLanguages.js) but it only manages monolingual text languages. It would make a lot of sense to align the two implementations so that a mistake like this is less likely to happen again.
Relevant line in Termbox: https://github.com/wikimedia/wikibase-termbox/blob/48e17a328e1695d127363899bccf978097a04890/src/client-entry.ts#L39