Configure swiftmailer to send messages to single recipient
When developing an application which sends email, you will often not want to actually send the email to the specified recipient during development.
You can configure via the extension configuration to send all email to a one ore more specific addresses.
Swift Mailer will add an extra header to the email, X-Swift-To, containing the replaced address, so you can still see who it would have been sent to.
You can also configure the extension to allow some exceptions, so the email will be really sent to the recipient if the address is whitelisted.