This MRF module supplements the MRF SimplePolicy reject rules by allowing specific users to be exempted from them.
You must configure the rejects under this policy module in order to have the exemptions work, and for performance reasons, the policy module should appear toward the end of your configured policy chain.
Example configuration which will block all users except for admin@example.com:
config :pleroma, :mrf_user_allowlist,
"example.com": ["https://example.com/users/admin"]