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Two accounts are not linked automatically (case sensitive issue)

Hello,

We’ve faced a particular issue with account linking on Auth0.
User was registered twice:

  1. Via Auth0 form with email a@test.com (example)
  2. Via Google sign in (linked as idp to Auth0) A@test.com

We have this rule configured on Auth0 - https://auth0.com/rules/link-users-by-email. And in case users from Auth0 and Google forms have exactly same email (e.g. a@test.com) it works perfectly fine. However it doesn’t work with two emails having different cases, looks like Auth0 treats them as 2 separate users.

As I’ve seen Auth0 automatically converts uppercase name in email to lowercase when using Auth0 form to signup. However it’s not the case when user is registered with Google as identity provider. Email of a user is still displayed as A@test.com and that’s probably the reason why merging is not working.

Therefore this looks to me like a bug as a behavior is very unexpected and this created an issue in our system.