Install extsmail by entering the following commands in the terminal:
sudo apt update sudo apt install extsmail
Description:
enables the robust sending of e-mail to external commands
extsmail masquerades as the standard UNIX sendmail program, reading messages, and later piping them to user-defined commands. . In a sense, extsmail can be thought of as a very simple "tiny" sendmail (Think SSMTP, UUCP, ...) . A typical use is to allow e-mail to be piped via ssh to external servers running a full sendmail-compatible MTA. extsmail is designed to have sensible defaults, and configuring it is a one-off, quick job.
Homepage: http://tratt.net/laurie/src/extsmail/
Version: 2.0-2.1
Section: universe/mail