My Jenkins installation uses the SAML plugin to delegate authentication to my IDP.

I am using just user authorization with Matrix Auth Plugin (not using any groups).

After upgrading to Matrix Auth Plugin 3.0, I tried to migrate the permissions as instructed, to explicitly be users (no ambiguity with groups).

For some reason, after I click on the 'user' icon to 'Migrate ambiguous permissions assignment to user xxxxxx', some (but not all) users in my job configurations get a red line crossed through them with 'User not found: xxxxxx'.

Is this attempt to enumerate the user an assumption that it is a 'local' user in the Jenkins database?

On another Jenkins instance I run, I use LDAP (not SAML) for the auth, and I didn't reproduce the problem there.

Given that I am using SAML, and the users are all defined externally, is this a harmless warning? It's very distracting though. I wasn't confident enough to apply the change as I didn't want to lock my users out

I'm posting it as a bug in case it's something either the SAML plugin or Matrix Auth need to accommodate when users are managed externally.

Please let me know if I can provide any other information.

Thanks!