The idea is to replace the Group.extend/Group.revokeExtend APIs with Group.addMember(group and Group.removeMember(group as it "group as members" would be easier to explain/understand than the Group inheritance concept.

To keep in consideration:

• The ability of extending a group is currently more limited than the ability of adding an account (see Group inheritance should not require membership on the parent group #1331)
• It might clash with Accept account id as param to Group.removeMember #1515