NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols.
STEPS TO REPRODUCE
1. network with 2 Kubuntu 22.04 machines mach1 and mach2
2. from mach1 smb://mach2/share
result is: could not connect to host for smb://mach2
access to mach2
(available in About System)
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Kernel Version" 5.15.0-33-generic (64 bits)
Graphic Platform: X11
if the target is a Kubuntu 20.04 machine, everything is fine and we can see shares!
if the target is a Windows system, everything is fine!
Just tested from Nemo:
Nemo can see Kubuntu 20.04 machine.
Nemo cannot see Kubuntu 22.04 machine.
Could not display "smb://mach2/share
Error: Failed to mount Windows share: Connection refused
Please select another viewer and try again
If it's broken from Nemo too, the issue is likely with the samba library itself. I would recommend that you report this to either the Kubuntu folks, or the Samba folks directly.