When we manually add new users to our OnPremise JIRA 6.3.9 via Administration > User management > Create, the newly created user is auto-assigned to one additional group, besides the obligatory jira-users group.
As far as we know, we never configured anything like an additional default group. We couldn't find any place in JIRA where we could have configured this.
Long story short: We don't want to auto-assign new users to this additional group. How can we switch this off? Any ideas? Is there any such thing as a list of default groups for newly added users?