Well, you define less levels than you need. Try this : %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \definesectionlevels [default] [ %chapter, % uncomment this line to make it work section, subsection, subsubsection, subsubsubsection, subsubsubsubsection] \starttext \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stoptext %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Interestingly, this will also work, although (if I’m counting correctly) there are still only 5 levels defined, but 6 are used (just like above): %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \definesectionlevels [default] [ %chapter, % uncomment this line to make it work section, subsection, subsubsection, subsubsubsection, subsubsubsubsection] \starttext \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel %\startsectionlevel %\stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stoptext %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Von: Sylvain Hubert Gesendet: Dienstag, 28. Mai 2024 10:48 An: mailing list for ConTeXt users Betreff: [NTG-context] lua error in `strc-lev.lua` ConTeXt LMTX version: 2024.05.27 18:16 Reproducible example: \definesectionlevels [default] [section, subsection, subsubsection, subsubsubsection, subsubsubsubsection] \starttext \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \startsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stopsectionlevel \stoptext lua error > lua error on line 19 in file ./input.tex: registered function call [969]: ...mtx/tex/texmf-context/tex/context/base/mkiv/strc-lev.lua:75: attempt to index a nil value (field '?') stack traceback: ...mtx/tex/texmf-context/tex/context/base/mkiv/strc-lev.lua:75: in function <...mtx/tex/texmf-context/tex/context/base/mkiv/strc-lev.lua:66> (...tail calls...)