Comment # 1 on bug 1174566 from Fabian Vogt

Judging by the logs, it seems like you have GNOME and Plasma installed next to
each other, both DEs have their services running. That can cause conflicts and
weird issues.

Jul 27 14:05:50 suse4Rocco.dom plasmashell[4905]: Aborting shell load: The
activity manager daemon (kactivitymanagerd) is not running.

Does krunner still work?
What happens when you run "qdbus-qt5 org.kde.ActivityManager" and
"/usr/lib64/libexec/kactivitymanagerd"?