To give some explanation of how Keycloak themes work, the theme used can be set for each realm, by default our system configures each realm to use the openremote theme, this theme is baked into our keycloak docker image.
To change the theme used by a realm using the UI you will need to use the keycloak admin UI /auth as our Manager UI Realms page doesn’t expose this - I will create an issue to change this.
The theme specified is then looked for in the /deployment/keycloak/themes dir of the keycloak container and if it cannot be found then the system falls back to using the openremote theme.