Received from Samuel Murray at 2/22/2019 11:41 AM UTC:
Is it possible for a member to "mute" replies from a specific other member?
Not currently possible using features available on Groups.io, but it's trivial to do if those wanting to block someone will choose to have all email sent to their home email address and then use a filter set up in their email client to block certain "From:" addresses.
Jim H