bug#66978: 30.0.50; crashed when closing one of two frames

[Gregor Zattler]

Hi Po,
* Po Lu <luangruo@yahoo.com> [2023-11-09; 07:52 +08]:
> The synchronous resource didn't take effect here, so the backtrace still
> doesn't fit the bill, I'm afraid.  I don't know if -xrm options are
> taken into account when Emacs is started in daemon mode, so perhaps try
> running:
>
>    (x-synchronize t)
>
> in a frame created by the daemon after it starts.  TIA.

I did.  It evaluated to `nil'!?

Then I was not able to reproduce the crash.  I now
re-tried with my usual configuration (and also with an
external monitor).  But no crash.

The doc string of x-synchronize warns of it's
performance penalty, but I do not experience one.
Might it be that the return value of nil indicates it
does not work at all in my case?

I put this expression in my everyday Emacs
configuration for now in the hope the problem will
re-surface some time.