I had `org-highlight-latex-and-related' set to `'(latex script))' and found that this (which triggers the running of `org-do-latex-and-related' ) seems to incur quite significant performance hits, especially with large Org files. (Even moreso, I think, if they have lots of headings - is a good example for this.) Running with Emacs 30.0.93 and Org-Mode 9.8-pre.