Right, I forgot about that feature. I have "Undetermined" as my language, but I also remember that I could set the language of the post. Maybe I accidentally set something there

edit: tried a few different things but I don't think it's the language. I set the language of the post to english, and my own language to english, and it wouldn't show up. I'd also like to note it wasn't possible for me to select all languages. well, I could select them, but all of them were deselected after pressing the save button.

edit 2: actually, it looks like I can select and save several languages, but only if I don't use ctrl+A to select them all. Also, it seems I can't actually save the changed language of the post

edit 3: it seems to me that I can save every language but one. If I try to save all languages, all get unselected, but it works if it is all languages minus one. And I still can't see the post properly in the community...