Your package quassel-irssi failed to build from source in current F28. https://koji.fedoraproject.org/koji/taskinfo?taskID=24886994 For details on mass rebuild see https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild
I had filed an upstream issue here: https://github.com/phhusson/quassel-irssi/issues/29 The build seems to fail due to -Werror=cast-function-type. I am not _entirely_ sure, but I believe this is a false positive; the cast that the compiler is complaining about seems to be how irssi's signals interface is meant to work. Turning off the warning and rebuilding the package doesn't seem to break anything, so I'm going to go ahead and build.
quassel-irssi-0-8.20171203git079be66.fc28 has been submitted as an update to Fedora 28. https://bodhi.fedoraproject.org/updates/FEDORA-2018-c0e3539662
quassel-irssi-0-8.20171203git079be66.fc28 has been pushed to the Fedora 28 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-c0e3539662
quassel-irssi-0-8.20171203git079be66.fc28 has been pushed to the Fedora 28 stable repository. If problems still persist, please make note of it in this bug report.