Email testing feature

It would be nice if a button could be added to each one of the email configurations in the the email configuration screen, which when clicked would send a test email to the admin, so that we can test this functionality without having to make a donation.

Yes. I agree that it would be nice feature. However, I think if you want to see the email, there is another way: Test the whole donation process in test mode and you will receive all emails to see these emails

Regards,

Tuan