"message": "(#200) If posting to a group, requires app being installed in the group

Question

I've created a test group and a test bot:

I own the group so I should be able to create an app that posts to the group.

The app is in developer mode. If I put it in production mode, I can't find it in the apps list:

How can I install the app to the group if it doesn't appears in the apps list? Because it already have "publish_to_groups" permission

To access that list I'm going to facebook group page -> group settings -> apps -> add apps