QEMU 7.2.0, -vnc :1, sasl=on ==> No matching security types (GTK-VNC SASL doesn't ring a bell)

[Frantisek Rysanek]

Dear fellow QEMU users,

I'm playing for the first time with the VNC output of QEMU.
I'm running qemu-system-x86_64 by hand from the command line, i.e. no 
virtmanager. No problems there, I know enough of QEMU's cmdline args 
to find my way about.
I'm compiling QEMU 7.2.0 from source.

The first time I used "-vnc :1" I chuckled that I got straight to the 
console of the VM guest = no auth.
Then I found the official note about VNC security:
https://qemu-project.gitlab.io/qemu/system/vnc-security.html

For the moment I'm too lazy to deal with SSL. I just tried this:

-vnc :1,sasl=on

Obviously I have saslauthd up and running, and coupled to PAM.

Curiously to me, of the three VNC clients that I've tried in Windows, 
none responded positively to the auth "algorithm set" offered by the 
QEMU VNC server. Such as, TigerVNC would just chirp 
"No matching security types".
Similarly TightVNC and UltraVNC.

Failing to find any relevant docs or forum posts, I've fired up 
Wireshark to take a look - and I've discovered that the QEMU VNC 
proposes a single "security type" called "GTK-VNC SASL".

The questions are probably obvious:

Is there a VNC client that would support this authentication method? 
:-)

Is there some way to enhance the QEMU VNC to propose other 
authentication methods, supported by some client counterparts?
Am I perhaps missing some compile-time option?
I probably still have GNUTLS turned off... maybe that's a missing 
dependency, which might add other security types?

To the authors/maintainers/contributors of QEMU: kudos and thanks a 
lot for the marvellous piece of software...

Thanks for your attention everybody.

Frank Rysanek