Is your feature request related to a problem? Please describe.

As the Keycloak-signin module does not create user we use user synchronization with our LDAP. Each user is subscribed to the same default space.
By default, all users receive a summary notification by email (as per default preferences), but it seems abnormal to us that a user who has never logged in receives an email notification.
We could disable the option in the default preferences or exclude this space from the mail notification, but we need the user to be notified when a new publication is posted without the need for the user to enable notification in their preferences.

Describe the solution you'd like

We would like the email notification were sent only if the user has authenticated at least once.

Describe alternatives you've considered

If not by default it could be thrue an option in the default preferences in the E-mail summary settings. For exemple