Dear List, I have done an little example with a \blackrule: \setuppapersize[A8,landscape] \setuplayout[leftmargin=2.5cm, leftmargindistance=0.2cm, backspace=2.9cm, width=4cm] \starttext \margintext{\blackrule[color=black, height=0.05ex, width=1cm]\\Me}\blackrule[color=black, height=0.05ex, width=4cm] \startformula a^n + b^n = c^n. \stopformula \stoptext My Question is , where to put margintext, with \dontleavethemode, with blackrule, because if I put it after \starttext: \margintext{\blackrule\\{Me}}\dontleavehmode\blackrule Before : \margintext{\blackrule[color=black, height=0.05ex, width=1cm]\\Me}\blackrule[color=black, height=0.05ex, width=4cm] there is no pdf after compiling. I get: Command Line: context.exe --synctex=-1 "pablo.tex" Startup Folder: C:\Users\Hermann\Downloads\context-mswin\tex\texmf-context\tex\context\test\mkiv resolvers | formats | executing runner 'run luametatex format': luametatex --jobname="./pablo.tex" --socket --shell-escape --fmt=C:/Users/Hermann/Downloads/context-mswin/tex/texmf-cache/luametatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/formats/luametatex/cont-en.fmt --lua=C:/Users/Hermann/Downloads/context-mswin/tex/texmf-cache/luametatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/formats/luametatex/cont-en.lui --c:currentrun=1 --c:fulljobname="./pablo.tex" --c:input="./pablo.tex" --c:kindofrun=1 --c:maxnofruns=9 --c:synctex="-1" --c:texmfbinpath="C:/Users/Hermann/Downloads/context-mswin/tex/texmf-mswin/bin" system > system > ConTeXt ver: 2023.09.03 19:03 LMTX fmt: 2023.9.4 int: english/english system > system > 'cont-new.mkxl' loaded open source > level 1, order 1, name 'C:/Users/Hermann/Downloads/context-mswin/tex/texmf-context/tex/context/base/mkxl/cont-new.mkxl' system > beware: some patches loaded from cont-new.mkiv close source > level 1, order 1, name 'C:/Users/Hermann/Downloads/context-mswin/tex/texmf-context/tex/context/base/mkxl/cont-new.mkxl' system > files > jobname './pablo', input './pablo.tex', result './pablo' fonts > latin modern fonts are not preloaded languages > language 'en' is active system > synctex functionality is enabled, expect 5-10 pct runtime overhead! open source > level 1, order 2, name './pablo.tex' modules > using user prefixed file 's-layout-show' modules > 's-layout-show' is loaded open source > level 2, order 3, name 'C:/Users/Hermann/Downloads/context-mswin/tex/texmf-context/tex/context/modules/mkxl/s-layout-show.mkxl' loading > ConTeXt Page Macros / Runtime Macros resolvers > lua > loading file 'C:/Users/Hermann/Downloads/context-mswin/tex/texmf-context/tex/context/base/mkiv/page-run.lua' succeeded close source > level 2, order 3, name 'C:/Users/Hermann/Downloads/context-mswin/tex/texmf-context/tex/context/modules/mkxl/s-layout-show.mkxl' fonts > beware: no fonts are loaded yet, using 'lm mono' in box pack quality > underfull hbox at line 7 in file './pablo.tex': (badness 1490) pack quality > underfull hbox at line 7 in file './pablo.tex': Me (badness 1448) tex error > tex error on line 7 in file ./pablo.tex: Undefined control sequence \margintext{\blackrule\\{Me}}\dontleavethemode \blackrule 1 \setuppapersize[A8,landscape] 2 \setuplayout[leftmargin=2.5cm, 3 leftmargindistance=0.5cm, 4 backspace=2.9cm, 5 width=4cm] 6 \showframe 7 >> \margintext{\blackrule\\{Me}}\dontleavethemode\blackrule 8 margintext{\blackrule[color=black, height=0.05ex, width=1cm]\\Me}\blackrule[color=black, height=0.05ex, width=4cm] 9 \starttext 10 \startformula 11 a^n + b^n = c^n. 12 \stopformula 13 \stoptext The control sequence at the end of the top line of your error message was never \def'ed. You can just continue as I'll forget about whatever was undefined. mtx-context | fatal error: return code: 1 _____________________________________________________________________ ConTeXt Compilation Report (Pages: 0) Errors: 0 Warnings: 0 Bad Boxes: 0 Thanks Uschi