Server rarely crashes when starting PyCharm (X Window System error)

[Rush-iam]

Describe the bug
I have used Xpra for ~6 months, and I sometimes get a server crash when I start PyCharm.
I estimate the probability as ~2%.
After the crash - PyCharm and Xvfb continue to work as background processes.

To Reproduce
xpra start --bind-ws=0.0.0.0:9999 pycharm

System Information (please complete the following information):

• Server OS: Ubuntu 18.04, Ubuntu 22.04
• Xpra Server Version 4.3.4, 4.4.3

Log:

(Xpra:4545): Gdk-ERROR **: 14:00:18.612: The program 'Xpra' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadWindow (invalid Window parameter)'.
  (Details: serial 1183 error_code 3 request_code 7 (core protocol) minor_code 0)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the GDK_SYNCHRONIZE environment
   variable to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
Info  | RdCoroutineScope          | 43:DefaultDispatcher-worker-25 | RdCoroutineHost overridden 

Complete log:
Xpra.log

Success run log: (run right after without crash)
Xpra_success.log

[totaam]

Xpra Server Version 4.3.4, 4.4.3

None of these versions are supported.
There is a very good chance that this bug is already fixed. Likely #3822 or even #3883