bug#69478: 30.0.50; Emacs dies after scrolling in eww

[Eli Zaretskii]

> Date: Sat, 02 Mar 2024 21:09:52 +0000
> From: Alexander Prähauser <ahprae@protonmail.com>
> Cc: Eli Zaretskii <eliz@gnu.org>, 69478@debbugs.gnu.org
> 
> "Po Lu" <luangruo@yahoo.com> writes:
> 
> >> (gdb) run -xrm 'Emacs.synchronous: true'
> >>
> >> from vterm in another Emacs instance. So I specified the flags inside
> >> gdb and I called emacs, not ./emacs. Could one of those two things be
> >> the culprit?
> >
> > No, but try executing:
> >
> >   (x-synchronize t)
> >
> > within the Emacs session after it starts.  This will enable synchronous
> > operation regardless of the command line with which Emacs was started.
> 
> Alright, this time I just ran emacs in gdb with logging on, evaluated
> (x-synchronize t), then visited a website. Interestingly, Emacs got
> froze again, instead of just crashing. Then I sent C-c in gdb, then
> exited gdb. I hope the backtrace works now.

Unfortunately, the backtrace still shows the error was processed
asynchronously.  I have no idea how this is possible.  Po Lu, did we
somehow circumvent the x-synchronize mechanism on the master branch?