No package groups in katello / foreman

Hi everybody,

I don't see package groups in repo content UI.
All packages are synced and on the detail page of a repository I see that
there are about 15000 packages, 4000 erratas and 202 package groups, but
when I click on the package groups, I get an empty view.
Also it is not possible to install a group on a subscriped host. yum
groupinstall "X Window System" gets an error message, that the group has no
packages.

Any hints?

Kind regards,
Christian