20201010, Tumbleweed, no additional repositories, fresh install, fresh dup

Procedure (German)
Hypervisor und Tools installieren
KVM-Server - KVM -Werkzeuge sind installiert

"Die KVM-Komponenten sind installiert. Auf dem Host k��nnen nun KVM-Gastsysteme
installiert werden."

Start: Virtual Machine Manager

Error messages:
The libvirtd service does not appear to be installed. Install and run the
libvirtd service to manage virtualization on this host.

Test:
systemctl status libvirtd 

Result:
lux-tw:~ # systemctl status libvirtd 
��� libvirtd.service - Virtualization daemon
     Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; vendor
preset: disabled)
     Active: inactive (dead) since Thu 2020-10-15 16:55:11 CEST; 4min 7s ago
TriggeredBy: ��� libvirtd.socket
             ��� libvirtd-ro.socket
             ��� libvirtd-admin.socket
       Docs: man:libvirtd(8)
             https://libvirt.org
    Process: 1258 ExecStart=/usr/sbin/libvirtd $LIBVIRTD_ARGS (code=exited,
status=0/SUCCESS)
   Main PID: 1258 (code=exited, status=0/SUCCESS)

Okt 15 16:53:11 lux-tw systemd[1]: Starting Virtualization daemon...
Okt 15 16:53:11 lux-tw libvirtd[1258]: libvirt version: 6.8.0
Okt 15 16:53:11 lux-tw libvirtd[1258]: hostname: lux-tw
Okt 15 16:53:11 lux-tw libvirtd[1258]: Failed to initialize libnetcontrol. 
Management of interface devices is d>
Okt 15 16:53:11 lux-tw systemd[1]: Started Virtualization daemon.
Okt 15 16:55:11 lux-tw systemd[1]: libvirtd.service: Succeeded.

Later compared installed packages to an existing and working installation on
Leap 15.2. I added the missing packetes, error messages remained