Automatically Add New Users To A Group

I realize I’m necro-posting here, but I have the same desire:

  • I have a group that I want only members of a group to be able to see, b/c I want to exclude members of a a smaller group (larger group is “activists” smaller group is “elected officials”)
  • I want to auto-add all new members to the main group (“activists”)

This would be solved by having what @zaino said in their OP.