We're trying to create user groups in Exchange Online in order to group users when applying permissions to specific folder on shared mailboxes.
We don't want to mail-enable those groups, but I don't seem to find way to do it. In Exchange, I can only create O365 Groups, distribution groups and security groups, which are all mail enabled. From Azure AD I can create a security group that's not mail enabled, but it doesn't appear anywhere when setting permissions to folders.
I'm probably missing something important where, but how should I proceed?