[keycloak-user] Realm Agnostic User Storage SPI

[Dmitriy Dmitriy]

Hi Guys,
I am a new keycloak user and have a question.

I have a multi-tenant use case and am using different realms/themes to keep
users segregated.  However I also need an ability to have a separate global
default view with all the users/realms without duplicating them across
realms for different application.

After doing some digging, my thoughts are to have a default realm use
custom User Storage SPI to enable additional user lookups that are not part
of the default realm.

My Questions:
1) Does this sound like I am on the right track or is there a better way of
looking at it?
2) Do you know if something similar already exists?
3) Do you see any potential issues with this approach?

Thank you,
Dmitriy