See https://github.com/picketlink2/picketlink-console/blob/master/gui/src/main/java/org/picketlink/as/console/client/ui/federation/FederationPresenter.java#L78

@ProxyCodeSplit
    @NameToken(NameTokens.FEDERATION)
    @SubsystemExtension(name = "Federation", group = "PicketLink", key = "logging")
    public interface MyProxy extends Proxy<FederationPresenter>, Place {
    }

The subsystem key refers to the name of the subsystem. This is how we deetct presencen of the subsystem and decide wether or not the extension should be displayed in the console.

The picketlink extension refers to "logging", but should instead refer to "picketlink".