TecMint published a tutorial about installing Roundcube Webmail on CentOS or RHEL 8/7.

How to Install Roundcube Webmail on CentOS/RHEL 8/7

Roundcube is a free and open-source, fully-featured web-based multilingual IMAP webmail software, with an application-like user interface that is fully functional and customizable, and uses the latest web standards.

How to Install Roundcube Webmail on CentOS/RHEL 8/7