[BUG] Admin fc-ac-theme pollutes logs

[olivierdepriester]

Describe the bug
When saving themes of a realm, the logs are polluted with warn and error messages due to the misconfiguration of fc-ac-theme. As this theme extends keycloak theme, it triggers the error because keycloak theme has no admin theme anymore. Maybe it would be better to remove the fc-ac-theme admin theme until there is a way to "extend" from the keycloak.v2 admin theme (I am not even sure this will happen)

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Realm Settings' > 'Themes'
2. Click on 'Save' button
3. See logs:

[exec] 2023-09-29 17:59:04,880 WARN  [executor-thread] org.keycloak.theme.DefaultThemeManager             : Not found parent theme 'keycloak' of theme 'fc-ac-theme'. Unable to load ADMIN theme 'fc-ac-theme' due to this.
[exec] 2023-09-29 17:59:04,880 ERROR [executor-thread] org.keycloak.theme.DefaultThemeManager             : Failed to find ADMIN theme fc-ac-theme, using built-in themes

Expected behavior
No logs should appear

Additional context

• Keycloak Version : 22.0.3

[clement-dufaure]

fixed in #105