An IDN is not accepted for Destination Email in Email Forward add form.

Summary

An IDN is not accepted for Destination Email in Email Forward add form. Punycode must be used. the displayed error is: The destination contains at least one invalid email address

Steps to reproduce

1. add an IDN (i.e. cuvée.com) as destination email in email forward form - produces error

Correct behaviour

it should be allowed as it is everywhere else on IspConfig3 latest, patched.

Environment

Server OS + version: Debian 10 and Debain 11 ISPConfig version: 3.2.8p1

Software version of the related software: Apache 2.4.53 7.4.30