On Wed, Mar 30, 2022 at 2:31 PM Jérôme LAURENS <jerome.laurens@u-bourgogne.fr> wrote:
https://www.pragma-ade.com/general/manuals/luatex.pdf
P210 the 3 last lines
"(obeys save stack)" also appears for set_synctex_line


ah ok, 1.10, an old one. 
This is the latest 
https://tug.org/svn/texlive/trunk/Master/texmf-dist/doc/luatex/base/
(trunk  should be https://tug.org/svn/texlive/tags/texlive-2022.0
 soon).

--
luigi