When I start IDM 3.5.1 I see errors on the console:

ERROR [MailEngine] NOtification email default -from- unspecified. Check
eDirectory setup.


I didn't setup any email config, nor do I want it to email anything to
anyone.

3.5.0 didn't squawk about this, and I don't remember seeing anything in
the 3.5.1 docs stating that email setup was mandatory.