Hi,
I'm new to ConTeXt and try to use the module typearea 
(https://modules.contextgarden.net/cgi-bin/module.cgi/action=find/name=typearea).
But the example doesn't work:

\usemodule[typearea]
\setupTypeArea[bcor=0mm,alphabets=3.1]
\setuppagenumbering[alternative=doublesided]
\starttext
\dorecurse4{\framed[width=\textwidth,height=\textheight]{test}\page}
\stoptext

I got:

texmf-dist/tex/context/third/typearea/t-typearea.tex'
loading         > Something like KOMA-TypeArea
tex error       > tex error on line 89 in file 
/usr/local/texlive/2023/texmf-dist/tex/context/third/typearea/t-typearea.tex: 
Missing number, treated as zero



<to be read again>

     {
<macro> \TA@alphabets
      \par \PageWidth =\dimexpr \paperwidth -\TA@bcor \relax \par \edef 
\Ratio {\withoutpt {
     \the \dimexpr 2\paperheight /(\PageWidth /32768)\relax }} \par 
\setbox \scratchbox \hbox {\dorecurse {26}{\character \recurselevel }} 
\Width =\dimexpr \TA@alphabet
<line 5.89>
     \setupTypeArea[bcor=0pt,oneside=no,alphabets=2.6]

79          height=\the\Height,
80          width=\the\Width,
81          header=2\lineheight,
82          headerdistance=\lineheight,
83          footer=2\lineheight,
84          footerdistance=3\lineheight,
85          topspace=\Top]
86     }
87     \protect
88
89 >>  \setupTypeArea[bcor=0pt,oneside=no,alphabets=2.6]
90
91     \doifnotmode{demo}{\endinput}
92
93     %D Usage example:
94     \usemodule[typearea]
95     \setupTypeArea[bcor=0mm,alphabets=3.1]
96     \setuppagenumbering[alternative=doublesided]
97     \starttext
98 \dorecurse4{\framed[width=\textwidth,height=\textheight]{test}\page}
99     \stoptext
A number should have been here; I inserted '0'. (If you can't figure out 
why I
needed to see a number, look up 'weird error' in the index to The TeXbook.)
mtx-context     | fatal error: return code: 1


Line 89 in the module should be the problem. But how can I solve it? I 
think some lines in the module should be commented out. (An example 
directly in the module?)

I thank you for any hint.

Greetings
Thomas