squirrelmail
webmail client written in php
SquirrelMail is a basic webmail package written in PHP4. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript) for maximum compatibility across browsers. It has very few requirements and is very easy to configure and install.
There is no official package available for openSUSE Leap 15.6Distributioner
Debian 9.0
RedHat RHEL-7
Unsupported distributions
The following distributions are not officially supported. Use these packages at your own risk.