Do you see an area that can be clarified or expanded, a technical inaccuracy, or a broken link? Please describe.
It is possible to get user object(s) from group object but this is not documented.
See #13298 for details.

Provide the URL or link to the exact page in the documentation to which you are referring.
https://docs.goauthentik.io/docs/users-sources/groups/group_ref#object-properties

Describe the solution you'd like
I would like to see the information gathered in #13298 documented in
https://docs.goauthentik.io/docs/users-sources/groups/group_ref#object-properties