Power Pages authentication settings: which one to change

This sheet compares Open registration, External login, Require unique email, OAuth 2.0 provider.

CriterionOpen registrationExternal loginRequire unique emailOAuth 2.0 provider
ControlsWhether anonymous visitors can self-create a local accountWhether users register or sign in with a third-party identityWhether a duplicate email is rejected at sign-upThird-party sign-in such as Google or Microsoft

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