Thank you for taking the time to make this write-up. Nicolas Goaziou <m...@nicolasgoaziou.fr> writes:
> With overlays, you can't have your cake > and eat it too. FWIW, I think Emacs has a branch (feature/noverlay) which has been reported to improve performance with overlays. AFAICT it's just hanging there waiting to be merged (though a naive "git merge" reveals some conflicts); some quick Googling suggests it has last been discussed two years ago: https://lists.gnu.org/archive/html/emacs-devel/2018-03/msg00565.html