kopano
Groupware server suite
Kopano provides email storage on the server side and brings its own Web-based mail client called WebApp. Kopano integrates with WebApp, Push clients and other mail services as an alternative to Microsoft Exchange and other comparable mail servers. Personal address book, calendar, notes and tasks, "Public Folders" and shared calendar functionalities (inviting internal and external users, resource management) can be handled by the software as well.
There is no official package available for openSUSE Leap 15.6Distributioner
openSUSE Leap 15.5
openSUSE Backports for SLE 15 SP4
SUSE SLE-15-SP1
Unsupported distributions
The following distributions are not officially supported. Use these packages at your own risk.