Configuration to Send or Restrict emails from specific SMTP User
The requirement to send emails to only specific domains under the particular SMTP user.
For example, an application using Mailgun configuration will trigger emails to @gmail.com, @yahoo.com, @hotmail.com, etc., domains.
But Mailgun needs to allow send emails only to @gmail.com and restrict sending emails to other domains.
Mailgun should have a feature to configure domains for both restricting and allowing for sending emails under a particular SMTP User.