bug#71644: 30.0.50; Severe slowdown in larger files with markers beginning in emacs 29+

[Eli Zaretskii <eliz@gnu.org>]

> Cc: mitchellahren@gmail.com, 71644@debbugs.gnu.org
> Date: Thu, 20 Jun 2024 19:11:28 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> 
> > From: Ihor Radchenko <yantar92@posteo.net>
> > Cc: Mitchell <mitchellahren@gmail.com>, 71644@debbugs.gnu.org
> > Date: Thu, 20 Jun 2024 13:49:10 +0000
> > 
> > Eli Zaretskii <eliz@gnu.org> writes:
> > 
> > > I cannot reproduce this on my system, with the current master branch,
> > > i.e. Emacs 30.  I _can_ reproduce this in Emacs 29.3, where indeed
> > > expanding any of the two abbrevs takes about 0.5 sec to show on the
> > > screen.  But in Emacs 30 it's instantaneous, even though I used an
> > > unoptimized build of Emacs 30.  Maybe the reason is that Emacs 30 now
> > > uses Org 9.7.4, whereas you have a local installation of 9.6.30?
> > 
> > What if you add
> > (setq org-fold-core-style 'text-properties) to your reproducer?
> 
> Then abbrevs don't work (not sure I understand why), so I cannot run
> the recipe.

Sorry, that was a cockpit error.  Now that I fixed that, I can report
that the setting you suggested doesn't change anything: I see no
delays in Emacs 30.