Hi,

Extensibility is definitely one of KeyCloak killer features, including the ability to extend and modify admin console behavior. Unfortunately, at the moment admin themes couldn't be extended with custom scripts, contrary to what is stated in the docs.

The issue has been known for months:
https://issues.jboss.org/browse/KEYCLOAK-3052
https://github.com/pedroigor/keycloak-authz/issues/26

 I've created a pull request, though the fix is trivial and could be reimplemented directly.
https://github.com/keycloak/keycloak/pull/2933

Cheers,
Mitya