We are currently running NC 18.0.12 on our own Server on Ubuntu. Since first Install we are using pw_auth (Unix User Backend) for User authentication. Unfortunately the pw_auth-App seems no longer in development. The most current release only supports up to NC 18. So we have to move to another auth-Backend for the new NC Versions.
I found a lot of information migrating to ldap, but that would be to much overhead for our server. So we would like to move to IMAP-Auth-App (https://github.com/nextcloud/user_external) or internal auth of NC. Our Users are using Calendar, Contacts, WebDAV (Files), Photos in NC.
I am looking for any hint how to migrate the users to another auth-backend without loosing data and without Import and Export Data for every single user.
Nextcloud version (eg, 18.0.2): 18.0.12
Operating system and version (eg, Ubuntu 20.04):18.04.5