When upgrading to libvirt 10.4-0 I can confirm that if /usr/sbin is in the PATH , the command : " virsh -c qemu:///session connect" works ; virt-manager can connect only after launching the virsh command.
- Bug#1072723: libvirt0: qemu:///session not connected after log... Michael Ott
- Bug#1072723: libvirt0: qemu:///session not connected afte... Francesco C
- Bug#1072723: libvirt0: qemu:///session not connected afte... Francesco C
- Bug#1072723: libvirt0: qemu:///session not connected afte... Francesco C

