[winswitch] Xpra shadow with Fedora 38

[Bob Babcock]

I did a fresh install of Fedora 38 KDE using nouveau video drivers. (Previously 
I was running Fedora 37 with 390xx proprietary drivers for my old video card.)  
At login, I now have the option of using Plasma X11 or Wayland.  I find xpra 
shadow doesn't send back anything to Windows 10 even if I picked X11 when 
logging on to Fedora.  Start also fails, but start-desktop works. Is this 
expected behavior?  Thanks.