Problem with groups in OpenHAB 3

[simoschip2000]

For me the library can not read the members of a group in OpenHAB 3. From what i have seen the members of a group are determined with these lines of code:
for i in json_data['members']: self.members[i['name']] = self.openhab.json_to_item(i)

When I access my servers REST interface with ip:8080/rest/items , I see that the group itself does not save its members. Instead each member remembers the groups it is in (see pictures).

Is this issue only occuring for me or is it a problem in general? I would try to fix it and commit if it is a problem in general.

Thank you!

A group thing:

A "normal" thing: