@prettygood@socially.drinkingatmy.computer did a horfix.
there is a problem with the JSON when no media is attached, so your API says nope.
Unfortunately my laptop is in juniors room who is falling asleep ATM and I know that I don't find time before Saturday or Sunday this weekend to properly fix the issue.

I try my best to find a solution asap.
it's only your pleroma instance I run into this weird bug, so it might take a minute or to to figure out what exactly is the issue, but I will try my best.

please ping me again when it stops to post.