Prevent "null" as email sender #7784
Description
If the :SystemEmail value does not contain a name, only an email address, and the user use contact form or the "Contact owner" form to send a mesage, the sender of the email will look like this:
null on behalf of name@example.com dataverse@example.edu
The guide says: "Note that only the email address is required", so Dataverse should handle both cases: when the name is supplied and when it isn't. Now the missing name ends up as "null" in the sent email.