Dear list, as Hraban already reported, there might be a bug in: \setupheadertexts[section][chapter][part][section] \starttext \dorecurse{10}{\part{Part} \chapter{Chapter} \dorecurse{5}{\section{Section}\page}} \stoptext Replacing [part] with [\getmarking{part}] gives the following error message: lua error > lua error on line 7 in file /home/ousia/a.tex: ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:413: attempt to compare nil with number stack traceback: ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:413: in function 'resolve' ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:524: in function 'doresolve' ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:552: in function <...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:548> ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:619: in function 'fetched' ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:657: in function 'fetchonemark' ...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:680: in function <...eta/tex/texmf-context/tex/context/base/mkiv/strc-mar.lua:675> 1 2 \setupheadertexts[section][chapter][\getmarking{part}][section] 3 4 \starttext 5 \dorecurse{10}{\part{Part} 6 \chapter{Chapter} 7 >> \dorecurse{5}{\section{Section}\page}} 8 \stoptext 9 Could you confirm whether this is a bug? (Hraban has already reported it.) Many thanks for your help, Pablo -- http://www.ousia.tk