Actually… I found a workaround.
1. Go to an old post and set the Medium plugin settings as if you were working with a brand new post.
2. Make some trivial change to the post. Add a trailing space at the end of a sentence, or something like that.
3. Push the change live.
The Medium plugin will kick in when the post is updated. Be aware, though, you can only do this once. For whatever reason, the plugin can’t be activated multiple times for the same post.
