Greetings!
It seems that OwnCloud and NextCloud might be unmaintained in Fedora. I found that upgrading my F27 box to F28 causes it to be unable to login:
https://bugzilla.redhat.com/show_bug.cgi?id=1562949
There are also CVEs open:
https://bugzilla.redhat.com/show_bug.cgi?id=1472720 https://bugzilla.redhat.com/show_bug.cgi?id=1451238
Additionally, F27 has an issue that prevents the calendar from working unless you downgrade one package to the F26 version:
https://bugzilla.redhat.com/show_bug.cgi?id=1525208
I don't think I have the expertise or time to step in and help, unfortunately, but these issues do seem bad for Fedora's users. If the maintainers no longer have time to maintain them, should we retire them? Is anyone else interested in stepping up to help out?