cyrus-imapd from home:buschmann23:cyrus:2.5 project
Select Your Operating System
Add repository and install manually
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:buschmann23:cyrus:2.5/15.5/home:buschmann23:cyrus:2.5.repo zypper refresh zypper install cyrus-imapd