It's possible to create a mail address user@gmail.com@nethdomain.tld which leads to a validation error when using that address as destination.
Steps to reproduce
- Create an address
user@gmail.com using a wildcard or set a domain

- The address
user@gmail.com@nethdomain.tld is created
- Create another address and set
user@gmail.com as destination
Expected behavior
The creation of user@gmail.com@nethdomain.tld is forbidden
Actual behavior
The creation of user@gmail.com@nethdomain.tld is allowed which leads to a validation error when using the same external mail address as destination.
Components
Mail 1.6.4
See also
https://community.nethserver.org/t/adding-external-alias-to-email-groups/25982/3?u=mrmarkuz
Thanks to Sergio
It's possible to create a mail address
user@gmail.com@nethdomain.tldwhich leads to a validation error when using that address as destination.Steps to reproduce
user@gmail.comusing a wildcard or set a domainuser@gmail.com@nethdomain.tldis createduser@gmail.comas destinationExpected behavior
The creation of
user@gmail.com@nethdomain.tldis forbiddenActual behavior
The creation of
user@gmail.com@nethdomain.tldis allowed which leads to a validation error when using the same external mail address as destination.Components
Mail 1.6.4
See also
https://community.nethserver.org/t/adding-external-alias-to-email-groups/25982/3?u=mrmarkuz
Thanks to Sergio