I agree with @tbrisker: deprecation warnings in the application are a good way to deal with it. We can easily provide installer instructions (foreman-installer --foreman-unattended true) to migrate beforehand.
Looks like I dropped the ball on this one.
Iād be happy to just clean up the code paths since I doubt anyone is still using it in production but just to be on the safe side I opened a PR adding a deprecation warning notification: https://github.com/theforeman/foreman/pull/8980
With the introduction of host registration there really is no reason to keep this around any more.
