Using "Private" repositories with Community Applications
( A "Private" repository is a repository which you are managing, but not making available to the community at large )
Since Unraid 6.0's introduction, so-called private repositories were supported via Docker - Template Repositories. With the advent of Community Applications, this method is deprecated.
Rather than working with an online repository, CA will fully support local private repositories. To accomplish this, save the applicable xml files within /config/plugins/community.applications/private/nameOfRepository/ on the flash drive. CA will read the contents of these folders (more than one is acceptable) every time it starts up. When private repositories are present, a new category within CA will appear "Private", and the apps can be browsed, installed etc from within there.
(Note that if you've also enabled dockerHub searching from within CA, then all installs from a dockerHub search will also appear within Private, namely "dockerHub Repository")
If you're looking to eventually publish to Community Applications, private repositories will allow you to see exactly how CA will render the xml's.