Description
In order to use namespaced attributes, currently you have to override the session service definition (documented here).

Being able to change the AttributeBag used without overriding the service definition would be good. This could be via a config setting or by decorating the existing service definition.

When overriding the service definition you have to explicitly make it public. I opened this issue after finding this was missing in the documentation. While updating the documentation fixes the problem, I feel there's a deeper problem.