Ah, I *think* I've figured it out. If you go to the sticker pack extension file in Xcode under the "General" tab there is a "Deployment Info" section, in there you can set whether it will work on iPhone and iPad, and now in recent Xcode there is also a "Mac" checkbox, so I think once that's checked and a build submitted that will be it.

Hi, yep, same here. I tried googling and all I found was this forum post! I wonder if we maybe just need to update the OS target for the sticker packs?