Hello,
first of all, the option Mail Alert option "When App is active" is marked, all mails are marked as read, no unread mail:
when I (again) read the NEWEST mail (in my sorting the top mail in the list) and in the background a new mail for THE SAME account comes in, there is no notification for the new mail (no sound, no popup, no icon in the top bar = complete silent).
When I read others mails in this account (second, third etc. mail in the list), there is a notification.
Also when a mail arrives in the second account, while I read the newest mail in the first account, notifications are also working.
And vice versa.
Greetings, Cimba
