Comment # 7 on bug 1203458 from Lin Ma

(In reply to Daniel Scott from comment #2)
> The last log entry was from August. However it updated when I ran it from
> the command line sudo virt-manager --debug
> 
> [Thu, 15 Sep 2022 10:50:17 virt-manager 15306] DEBUG (cli:204) Version 4.1.0
> launched with command line: /usr/bin/virt-manager --debug
> [Thu, 15 Sep 2022 10:50:17 virt-manager 15306] DEBUG (virtmanager:170)
> virt-manager version: 4.1.0
> [Thu, 15 Sep 2022 10:50:17 virt-manager 15306] DEBUG (virtmanager:171)
> virtManager import: /usr/share/virt-manager/virtManager
> [Thu, 15 Sep 2022 10:50:17 virt-manager 15306] DEBUG (cli:195) Uncaught
> exception:
> Traceback (most recent call last):
>   File "/usr/bin/virt-manager", line 8, in <module>
>     virtmanager.runcli()
>   File "/usr/share/virt-manager/virtManager/virtmanager.py", line 274, in
> runcli
>     main()
>   File "/usr/share/virt-manager/virtManager/virtmanager.py", line 198, in
> main
>     leftovers = _import_gtk(leftovers)
>   File "/usr/share/virt-manager/virtManager/virtmanager.py", line 73, in
> _import_gtk
>     raise Exception("Error starting virt-manager: No graphical display
> found")
> Exception: Error starting virt-manager: No graphical display found

This is normal because sudo doesn't switch environment variables.
You need to switch to privileged user with environment variables instead of
sudo.
E.g.
suse@twhost:~> su -
Password: 
twhost:~ # virt-manager --debug


(In reply to Daniel Scott from comment #4)
> I did this as user, super user, and with sudo
> 
> dos@DOS1:~> echo $DISPLAY
> :0
> dos@DOS1:~> sudo su
> [sudo] password for root: 
> DOS1:/home/dos # echo $display
> 
> DOS1:/home/dos # exit
> exit
> dos@DOS1:~> sudo echo $display
> 
> dos@DOS1:~>
> 
> So I tried running virt-manager as user, and that produced the GUI, and
> after opening the VM and running it, crashed with the following log info
> located in
> /home/dos/.cache/virt-manager

I havn't figured out any abnormal message in the log info in comment#4,
Everything looks good.

And I can't reproduce this issue on my tumbleweed host, my host os info is:

suse@twhost:~> cat /etc/os-release 
NAME="openSUSE Tumbleweed"
# VERSION="20220914"
ID="opensuse-tumbleweed"
ID_LIKE="opensuse suse"
VERSION_ID="20220914"
PRETTY_NAME="openSUSE Tumbleweed"
ANSI_COLOR="0;32"
CPE_NAME="cpe:/o:opensuse:tumbleweed:20220914"
BUG_REPORT_URL="https://bugs.opensuse.org"
HOME_URL="https://www.opensuse.org/"
DOCUMENTATION_URL="https://en.opensuse.org/Portal:Tumbleweed"
LOGO="distributor-logo-Tumbleweed"

suse@twhost:~> uname -r
5.19.8-1-default

suse@twhost:~> virt-manager --version
4.1.0

suse@twhost:~> sudo libvirtd --version
libvirtd (libvirt) 8.7.0

Is it 100% reproducible on your updated tumbleweed host?