What happened?

If users are created from a plugin (e.g. OIDC), the system sends user creation notifications to the anonymous user (anonymous@example.org).

What should happen?

Do not send Emails to the anonymous user.

How can this be reproduced?

Use a plugin, that internally creates users, e.g. OIDC or SAML. If you watch the smtp log on the server, you can see, that there is an email send to the anonymous user's email address, which is anonymous@example.org by default.
This seems to be the reason - if not a user, but the system itself creates a user, it falls back to anonymous:

Matomo version

all

PHP version

No response

Server operating system

No response

What browsers are you seeing the problem on?

No response

Computer operating system

No response

Relevant log output

No response

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