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diff --git a/tex/context/base/mkxl/anch-box.mkxl b/tex/context/base/mkxl/anch-box.mkxl
new file mode 100644
index 000000000..570f8862d
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+++ b/tex/context/base/mkxl/anch-box.mkxl
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+%D \module
+%D   [       file=anch-box,
+%D        version=2022.03.25,
+%D          title=\CONTEXT\ Anchoring Macros,
+%D       subtitle=Boxes,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
+%C
+%C This module is part of the \CONTEXT\ macro||package and is
+%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
+%C details.
+
+\writestatus{loading}{ConTeXt Anchoring Macros / Boxes}
+
+\unprotect
+
+\startMPpositiongraphic{mypos:boxanchor:arrow}{}% from,to,linecolor,text,alternative,leftedge,rightedge,distance}
+    anch_box_arrows_draw ;
+\stopMPpositiongraphic
+
+\tolerant\permanent\protected\def\connectboxanchors[#1]#*[#2]#*[#3]#*[#4]#*#:#5#6%
+  {\begingroup
+   \defineboxanchor[#5]%
+   \setboxanchor[#5][#1][#3]\hpack{\xypos{\namespacedboxanchor{#5}}}%
+   \ifparameter#3\or\setupboxanchorcontent[#1][#3]\fi
+   \defineboxanchor[#6]%
+   \setboxanchor[#6][#2][#4]\hpack{\xypos{\namespacedboxanchor{#6}}}%
+   \ifparameter#4\or\setupboxanchorcontent[#1][#4]\fi
+   \startpositionoverlay{text-1}% will become configurable region
+     \setMPpositiongraphic
+       {\namespacedboxanchor{#5}}%
+       {\namedboxanchorcontentparameter{#1}\c!mp}%
+       {from=\namespacedboxanchor{#5},%
+        to=\namespacedboxanchor{#6},%
+        distance={\namedboxanchorcontentparameter{#1}\c!distance},%
+        dashtype={\namedboxanchorcontentparameter{#1}\c!dash},%
+        alternative={\namedboxanchorcontentparameter{#1}\c!alternative},%
+        text={\namedboxanchorcontentparameter{#1}\c!text},%
+        rulethickness={\namedboxanchorcontentparameter{#1}\c!rulethickness},%
+        linecolor=\namedboxanchorcontentparameter{#1}{\c!rulecolor}}%
+   \stoppositionoverlay
+   \endgroup}
+
+% dedicated or not
+
+\tolerant\permanent\protected\def\connectmatrixanchors[#1]#*[#2]#*[#3]#*[#4]#*#:#5#6%
+  {\begingroup
+   \doifelseinset{#5}{\m_anch_matrix_list}\donetrue\donefalse
+   \ifdone\else
+     \defineboxanchor[#5]%
+     \setboxanchor[#5][#1][#3]\hpack{\xypos{\namespacedboxanchor{#5}}}%
+     \xdef\m_anch_matrix_list{\m_anch_matrix_list,#5}%
+   \fi
+   \ifparameter#3\or\setupboxanchorcontent[#1][#3]\fi
+   \doifelseinset{#6}{\m_anch_matrix_list}\donetrue\donefalse
+   \ifdone\else
+     \defineboxanchor[#6]%
+     \setboxanchor[#6][#2][#4]\hpack{\xypos{\namespacedboxanchor{#6}}}%
+     \xdef\m_anch_matrix_list{\m_anch_matrix_list,#6}%
+   \fi
+   \ifparameter#4\or\setupboxanchorcontent[#1][#4]\fi
+   \startpositionoverlay{text-1}% will become configurable region
+     \setMPpositiongraphic
+       {\namespacedboxanchor{#5}}%
+       {\namedboxanchorcontentparameter{#1}\c!mp}%
+       {from=\namespacedboxanchor{#5},%
+        to=\namespacedboxanchor{#6},%
+        distance={\namedboxanchorcontentparameter{#1}\c!distance},%
+        dashtype={\namedboxanchorcontentparameter{#1}\c!dash},%
+        alternative={\namedboxanchorcontentparameter{#1}\c!alternative},%
+        text={\namedboxanchorcontentparameter{#1}\c!text},%
+        rulethickness={\namedboxanchorcontentparameter{#1}\c!rulethickness},%
+        linecolor=\namedboxanchorcontentparameter{#1}{\c!rulecolor},%
+        % matrix specific:
+        leftedge=\namespacedboxanchor\c!leftedge,%
+        rightedge=\namespacedboxanchor\c!rightedge}%
+   \stoppositionoverlay
+   \endgroup}
+
+\let\m_anch_matrix_list\empty
+
+\tolerant\permanent\protected\def\startmatrixanchors
+  {\glet\m_anch_matrix_list\empty
+   \defineboxanchor[\v!leftedge]%
+   \setboxanchor[\v!leftedge][\v!leftedge]\hpack{\xypos{\namespacedboxanchor\v!leftedge}}%
+   \defineboxanchor[\v!rightedge]%
+   \setboxanchor[\v!rightedge][\v!rightedge]\hpack{\xypos{\namespacedboxanchor\v!rightedge}}%
+   \setupmathfence[\c!leftsource=\v!leftedge,\c!rightsource=\v!rightedge]}
+
+\tolerant\permanent\protected\def\stopmatrixanchors
+  {\setupmathfence[\c!leftsource=,\c!rightsource=]%
+   \glet\m_anch_matrix_list\empty}
+
+
+\defineboxanchorcontent
+  [arrow]
+  [\c!mp=mypos:boxanchor:arrow,
+   \c!distance=1.5\exheight,
+   \c!rulethickness=\linewidth,
+   \c!rulecolor=textcolor]
+
+\defineboxanchorcontent
+  [\v!top]
+  [arrow]
+  [\c!corner=\v!height,
+   \c!location=\v!depth,
+   \c!yoffset=.25\exheight,
+   \c!alternative=\v!top]
+
+\defineboxanchorcontent
+  [\v!bottom]
+  [arrow]
+  [\c!corner=\v!depth,
+   \c!location=\v!height,
+   \c!yoffset=-\namedboxanchorcontentparameter{top}\c!yoffset,
+   \c!alternative=\v!bottom]
+
+\defineboxanchorcontent
+  [\v!left]
+  [arrow]
+  [\c!corner={\v!middle,\v!left},
+   \c!xoffset=-1.25\emwidth,
+   \c!alternative=\v!left]
+
+\defineboxanchorcontent
+  [\v!right]
+  [arrow]
+  [\c!corner={\v!middle,\v!right},
+   \c!xoffset=-\namedboxanchorcontentparameter{left}\c!xoffset,
+   \c!alternative=\v!right]
+
+\defineboxanchorcontent
+  [\v!leftedge]
+  [\v!left]
+  [\c!xoffset=-.25\exheight]
+
+\defineboxanchorcontent
+  [\v!rightedge]
+  [\v!right]
+  [\c!xoffset=0.25\exheight] % we are centered
+
+\defineboxanchorcontent[\v!middle:\v!bottom][\v!bottom][\c!alternative=\v!middle,\c!yoffset=-.5\exheight]
+\defineboxanchorcontent[\v!middle:\v!top   ][\v!top   ][\c!alternative=\v!middle,\c!yoffset=.5\exheight]
+\defineboxanchorcontent[\v!middle:\v!left  ][\v!left  ][\c!alternative=\v!middle,\c!xoffset=-.5\exheight]
+\defineboxanchorcontent[\v!middle:\v!right ][\v!right ][\c!alternative=\v!middle,\c!xoffset=.5\exheight]
+
+\defineboxanchorcontent
+  [\v!left:\v!bottom]
+  [\v!bottom]
+  [\c!alternative=\v!middle,
+   \c!corner={\v!left,\v!depth},
+   \c!xoffset=-.25\exheight,
+   \c!yoffset=-.25\exheight]
+
+\defineboxanchorcontent
+  [\v!right:\v!bottom]
+  [\v!bottom]
+  [\c!alternative=\v!middle,
+   \c!corner={\v!right,\v!depth},
+   \c!xoffset=.25\exheight,
+   \c!yoffset=-.25\exheight]
+
+\defineboxanchorcontent
+  [\v!left:\v!top]
+  [\v!top]
+  [\c!alternative=\v!middle,
+   \c!corner={\v!left,\v!height},
+   \c!xoffset=-.25\exheight,
+   \c!yoffset=.25\exheight]
+
+\defineboxanchorcontent
+  [\v!right:\v!top]
+  [\v!top]
+  [\c!alternative=\v!middle,
+   \c!corner={\v!right,\v!height},
+   \c!xoffset=.25\exheight,
+   \c!yoffset=.25\exheight]
+
+\protect