Hi Rudolf, After playing around with the generated LaTeX in overleaf, I have to conclude that the problem is that ALT_TITLE should be not generated for unnumbered chapters, sections, etc. As far as my LaTeX goes, you use the [alt_title] to get something different in the TOC, so it makes no sense and LaTeX doesn’t cater for it.
Solutions from the org-mode side: 1. You don’t use ALT_TITLE if section is unnumbered (easier) 2. We make org-mode throw an error in this case (???) Discussion open ;-) Seasons greetings, /PA
