Hello, I recently attempted switching to a custom domain but (hastily) bailed on it because the app wasn't sending emails properly. This is typically what I would get:
smtplib.SMTPResponseException: (451, b'4.4.2 Timeout - closing connection. l66sm16594711qte.48 - gsmtp')
I went back to using "username.pythonanywhere.com" for my website and the proper handing of emails was restored.
Was I too hasty? What might be the cause of the difference between the two settings? If it helps, I was using NameCheap for my custom domain. (My custom domain worked perfectly aside from this issue with email.)