Oh yeah, sorry. I didn’t mention that the API isn’t available on production sites like piefed.social. I’ve been messing around with a build of Thunder on my dev instance, and - among other things - the app doesn’t uses the same V3 endpoint that Lemmy does, so it’d always need to be a different version than the one that’s currently available for Lemmy.
This is all quite old drama, and the issue itself is fixed now, but at one point someone kicked off about how if you uploaded a picture to Lemmy, there was no easy way to delete it (you could delete your post, but the image would still be there at whatever URL was created for it, and it wasn’t even that easy for admins to find and remove it) - so I’m guessing that it stems from that.