Allow a notification to bypass the content access check

Patch attached.

+1 for this idea.

In our case, we need to send a thank you email to anonymous users without any links so the access check shouldn't even need to run.

I applied the patch on a new site with the module and the new configuration property bypass_anonymous_access was saved on the notification configuration entity, but on an existing site, it doesn't seem to persist.

Perhaps an update hook is also required to add the property and set it to false on existing notifications?

+1 for this.

I'd also suggest adding extra info to the form-item "Adhoc email addresses" that these emails gets validated against existing users, if the checkbox from this feature is not checked. This is not clear and for non-tech users this might be difficult to find out :-)