Groups claim does not include access to shared groups

I want to use GitLab as OAuth2/OpenID Connect identity provider.
In our client platform (Polarion), we have the option to synchronize group membership of users with the identity provider.

I now want to achieve the following:
Setup the following groups:

  • Group1
  • Group2
  • GroupAll (by inviting Group1 and Group2 to this group)

This way I have team specific groups Group1 and Group2 and a further group GroupAll that automatically consists of all group members. The GroupAll with then be given generic access in Polarion and the other groups the more specific access.

In the example above, my user is a direct member of Group1 and since Group1 is invited to GroupAll, he also has access there.

When I now check the groups claim as defined here, it only returns Group1 and not GroupAll.

Is there a way to see all groups to which a user has access to, including groups where he got access by one of his groups being invited to?

We have a self managed v16.5.1-ee.