I have created a M365 security group hoping to be able to assign that group to a SharePoint Online group in a classic team site. It doesnt show up in the People and Groups -> Add users -> Invite people dialog. I thought this should be possible, but suspecting I am misunderstanding some part. Does this only work for synced local AD groups? Should I create a AAD security group? Should i be patient for the M365 security group to become available to SPO (created it > 8 hours ago)?