I automatically got Hebrew because that’s what my phone is set to. The interface strings have some mistakes, bit I guess I can fix it in Transifex. A much bigger problem is that almost everything is shown right to left, including English content.
MediaWiki had a similar problem until 2011, but it was fixed, mostly by the amazing SPQRobin.
Until it’s fixed in Discourse, I guess I’ll have to use it in Belarusian or something.