Allows to restrict destination domains where we want send emails to. You can specify more than one domain by using comma separator. Destination email must end with one of listed stings when this option specified
Example: @domain1.com,domain2.com
- tt>@domain1.com - any email matching *@domain1.com is allowed
- domain2.com - any email matching *@*.domain2.com is allowed,
like: user1@domain2.com, user2@sub.domain2.com, user3@sub.sub.domain2.com