Narrowing things down. I can post a photo to Known from my desktop with OS X. I don’t expect it to show up on micro.blog: stream.jeremycherfas.net
@jeremycherfas I think micro.blog only extracts photos from posts that doesn't have a title and that are 280 characters or less in length. Posts with titles only gets displayed as the title and a link back to the post.
@jeremycherfas It seems like your software gives untitled posts a title, "untitled". I've had to battle various WordPress themes trying to do the same thing. It's quite anoying when it happens.
@MrHenko Yes. I remember all the discussion about WordPress doing that. But I didn't think it would affect me.