2022-04-01 09:35:00

53 files changed, 1208 insertions, 445 deletions

diff --git a/tex/context/base/mkii/cont-new.mkii b/tex/context/base/mkii/cont-new.mkii
index 4b51600b4..382032446 100644
--- a/tex/context/base/mkii/cont-new.mkii
+++ b/tex/context/base/mkii/cont-new.mkii
@@ -11,7 +11,7 @@
 %C therefore copyrighted by \PRAGMA. See mreadme.pdf for
 %C details.
 
-\newcontextversion{2022.03.24 21:14}
+\newcontextversion{2022.04.01 09:33}
 
 %D This file is loaded at runtime, thereby providing an
 %D excellent place for hacks, patches, extensions and new
diff --git a/tex/context/base/mkii/context.mkii b/tex/context/base/mkii/context.mkii
index ac446c2e1..433b62f7e 100644
--- a/tex/context/base/mkii/context.mkii
+++ b/tex/context/base/mkii/context.mkii
@@ -20,7 +20,7 @@
 %D your styles an modules.
 
 \edef\contextformat {\jobname}
-\edef\contextversion{2022.03.24 21:14}
+\edef\contextversion{2022.04.01 09:33}
 
 %D For those who want to use this:
 
diff --git a/tex/context/base/mkiv/char-def.lua b/tex/context/base/mkiv/char-def.lua
index aa6353297..b4f07a529 100644
--- a/tex/context/base/mkiv/char-def.lua
+++ b/tex/context/base/mkiv/char-def.lua
@@ -63063,34 +63063,42 @@ characters.data={
  },
  [0x2061]={
   category="cf",
-  comment="maybe: nulloperator",
+  comment="ordinary",
   description="FUNCTION APPLICATION",
   direction="bn",
   linebreak="al",
+  mathclass="ghost",
+  mathname="applyfunction",
   unicodeslot=0x2061,
  },
  [0x2062]={
   category="cf",
+  comment="binary",
   description="INVISIBLE TIMES",
   direction="bn",
   linebreak="al",
+  mathclass="ghost",
+  mathname="invisibletimes",
   unicodeslot=0x2062,
  },
  [0x2063]={
   category="cf",
+  comment="punctuation",
   description="INVISIBLE SEPARATOR",
   direction="bn",
   linebreak="al",
-  mathclass="binary",
-  mathname="invisibletimes",
-  synonyms={ "invisible comma" },
+  mathclass="ghost",
+  mathname="invisiblecomma",
   unicodeslot=0x2063,
  },
  [0x2064]={
   category="cf",
+  comment="binary",
   description="INVISIBLE PLUS",
   direction="bn",
   linebreak="al",
+  mathclass="ghost",
+  mathname="invisibleplus",
   unicodeslot=0x2064,
  },
  [0x2066]={
diff --git a/tex/context/base/mkiv/cont-new.mkiv b/tex/context/base/mkiv/cont-new.mkiv
index 883269f4b..feaee9df4 100644
--- a/tex/context/base/mkiv/cont-new.mkiv
+++ b/tex/context/base/mkiv/cont-new.mkiv
@@ -13,7 +13,7 @@
 
 % \normalend % uncomment this to get the real base runtime
 
-\newcontextversion{2022.03.24 21:14}
+\newcontextversion{2022.04.01 09:33}
 
 %D This file is loaded at runtime, thereby providing an excellent place for hacks,
 %D patches, extensions and new features. There can be local overloads in cont-loc
diff --git a/tex/context/base/mkiv/context.mkiv b/tex/context/base/mkiv/context.mkiv
index 7f27d0ba5..b5e27e63e 100644
--- a/tex/context/base/mkiv/context.mkiv
+++ b/tex/context/base/mkiv/context.mkiv
@@ -49,7 +49,7 @@
 %D {YYYY.MM.DD HH:MM} format.
 
 \edef\contextformat {\jobname}
-\edef\contextversion{2022.03.24 21:14}
+\edef\contextversion{2022.04.01 09:33}
 
 %D Kind of special:
 
diff --git a/tex/context/base/mkiv/math-act.lua b/tex/context/base/mkiv/math-act.lua
index 4e3365d74..80f58020d 100644
--- a/tex/context/base/mkiv/math-act.lua
+++ b/tex/context/base/mkiv/math-act.lua
@@ -169,7 +169,7 @@ function mathematics.overloadparameters(target,original)
                                     report_math("overloading math parameter %a: %S => %S",name,oldvalue,newvalue)
                                 end
                             else
-                                report_math("invalid math parameter %a",name)
+                             -- report_math("invalid math parameter %a",name)
                             end
                             mathparameters[name] = newvalue
                         end
diff --git a/tex/context/base/mkiv/mult-low.lua b/tex/context/base/mkiv/mult-low.lua
index f24c66d12..12f8ecfbe 100644
--- a/tex/context/base/mkiv/mult-low.lua
+++ b/tex/context/base/mkiv/mult-low.lua
@@ -205,6 +205,9 @@ return {
         "breakafterdirnormalizecode", "removemarginkernsnormalizecode", "clipwidthnormalizecode", "flattendiscretionariesnormalizecode",
         "discardzerotabskipsnormalizecode", "flattenleadersnormalizecode",
         --
+        "nopreslackclassoptioncode", "nopostslackclassoptioncode",
+        "lefttopkernclassoptioncode", "righttopkernclassoptioncode", "leftbottomkernclassoptioncode", "rightbottomkernclassoptioncode",
+        --
         "noligaturingglyphoptioncode", "nokerningglyphoptioncode", "noleftligatureglyphoptioncode",
         "noleftkernglyphoptioncode", "norightligatureglyphoptioncode", "norightkernglyphoptioncode",
         "noexpansionglyphoptioncode", "noprotrusionglyphoptioncode", "noitaliccorrectionglyphoptioncode",
@@ -462,6 +465,8 @@ return {
         --
         "getfirstcharacter", "doifelsefirstchar", "doiffirstcharelse",
         --
+        "mathclassvalue",
+        --
         "startnointerference", "stopnointerference",
         --
         "twodigits","threedigits",
@@ -534,7 +539,7 @@ return {
         "superprescript", "subprescript", "nosuperprescript", "nosubsprecript",
         --
         "uncramped", "cramped",
-        "mathstyletrigger", "triggermathstyle",
+        "mathstyletrigger", "triggermathstyle", "triggeredmathstyle",
         "mathstylefont", "mathsmallstylefont", "mathstyleface", "mathsmallstyleface", "mathstylecommand", "mathpalette",
         "mathstylehbox", "mathstylevbox", "mathstylevcenter", "mathstylevcenteredhbox", "mathstylevcenteredvbox",
         "mathtext", "setmathsmalltextbox", "setmathtextbox",
diff --git a/tex/context/base/mkiv/mult-prm.lua b/tex/context/base/mkiv/mult-prm.lua
index b366ea336..5bdea77de 100644
--- a/tex/context/base/mkiv/mult-prm.lua
+++ b/tex/context/base/mkiv/mult-prm.lua
@@ -166,6 +166,7 @@ return {
   "Umathskeweddelimitertolerance",
   "Umathskewedfractionhgap",
   "Umathskewedfractionvgap",
+  "Umathsource",
   "Umathspaceafterscript",
   "Umathspacebeforescript",
   "Umathstackdenomdown",
@@ -237,6 +238,8 @@ return {
   "aftergrouped",
   "aliased",
   "alignmark",
+  "alignmentcellsource",
+  "alignmentwrapsource",
   "aligntab",
   "allcrampedstyles",
   "alldisplaystyles",
@@ -466,11 +469,13 @@ return {
   "mathforwardpenalties",
   "mathfrac",
   "mathghost",
+  "mathleftclass",
   "mathlimitsmode",
   "mathmiddle",
   "mathnolimitsmode",
   "mathpenaltiesmode",
   "mathrad",
+  "mathrightclass",
   "mathrulesfam",
   "mathrulesmode",
   "mathscale",
diff --git a/tex/context/base/mkiv/status-files.pdf b/tex/context/base/mkiv/status-files.pdf
index 3f451abe0..eb82f9913 100644
--- a/tex/context/base/mkiv/status-files.pdf
+++ b/tex/context/base/mkiv/status-files.pdf
diff --git a/tex/context/base/mkiv/status-lua.pdf b/tex/context/base/mkiv/status-lua.pdf
index b642259b7..76485d6f9 100644
--- a/tex/context/base/mkiv/status-lua.pdf
+++ b/tex/context/base/mkiv/status-lua.pdf
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
--- /dev/null
+++ b/tex/context/base/mkxl/anch-box.mkxl
@@ -0,0 +1,180 @@
+%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
diff --git a/tex/context/base/mkxl/cont-new.mkxl b/tex/context/base/mkxl/cont-new.mkxl
index 6f4698847..8f4d6c1cf 100644
--- a/tex/context/base/mkxl/cont-new.mkxl
+++ b/tex/context/base/mkxl/cont-new.mkxl
@@ -13,7 +13,7 @@
 
 % \normalend % uncomment this to get the real base runtime
 
-\newcontextversion{2022.03.24 21:14}
+\newcontextversion{2022.04.01 09:33}
 
 %D This file is loaded at runtime, thereby providing an excellent place for hacks,
 %D patches, extensions and new features. There can be local overloads in cont-loc
diff --git a/tex/context/base/mkxl/context.mkxl b/tex/context/base/mkxl/context.mkxl
index 6beb0171b..2c1cccae3 100644
--- a/tex/context/base/mkxl/context.mkxl
+++ b/tex/context/base/mkxl/context.mkxl
@@ -29,7 +29,7 @@
 %D {YYYY.MM.DD HH:MM} format.
 
 \immutable\edef\contextformat {\jobname}
-\immutable\edef\contextversion{2022.03.24 21:14}
+\immutable\edef\contextversion{2022.04.01 09:33}
 
 %overloadmode 1 % check frozen / warning
 %overloadmode 2 % check frozen / error
@@ -584,6 +584,8 @@
 \loadmkxlfile{meta-blb}
 \loadmkxlfile{grph-epd}
 
+\loadmkxlfile{anch-box}
+
 \loadmkxlfile{typo-shp}
 
 \loadmkxlfile{math-inc} % an experiment
diff --git a/tex/context/base/mkxl/font-con.lmt b/tex/context/base/mkxl/font-con.lmt
index b36f18dfa..83b97847d 100644
--- a/tex/context/base/mkxl/font-con.lmt
+++ b/tex/context/base/mkxl/font-con.lmt
@@ -713,7 +713,7 @@ function constructors.scale(tfmdata,specification)
                     local tl = mk.topleft
                     local br = mk.bottomright
                     local bl = mk.bottomleft
-                    chr.mathkern = { -- singular -> should be patched in luatex !
+                    chr.mathkerns = {
                         topright    = tr and mathkerns(tr,vdelta) or nil,
                         topleft     = tl and mathkerns(tl,vdelta) or nil,
                         bottomright = br and mathkerns(br,vdelta) or nil,
@@ -727,6 +727,22 @@ function constructors.scale(tfmdata,specification)
                     chr.italic = vi*hdelta
                 end
             end
+            local vk = character.topleft
+            if vk and vk ~= 0 then
+                chr.topleft = vk*hdelta
+            end
+            local vk = character.topright
+            if vk and vk ~= 0 then
+                chr.topright = vk*hdelta
+            end
+            local vk = character.bottomleft
+            if vk and vk ~= 0 then
+                chr.bottomleft = vk*hdelta
+            end
+            local vk = character.bottomright
+            if vk and vk ~= 0 then
+                chr.bottomright = vk*hdelta
+            end
          -- local ft = character.options
          -- if ft then
          --     chr.options = ft
diff --git a/tex/context/base/mkxl/font-imp-tracing.lmt b/tex/context/base/mkxl/font-imp-tracing.lmt
index 749a3c964..3de48af6f 100644
--- a/tex/context/base/mkxl/font-imp-tracing.lmt
+++ b/tex/context/base/mkxl/font-imp-tracing.lmt
@@ -190,9 +190,9 @@ local function initialize(tfmdata,key,value)
             local blcolor     = { "startcolor", "trace:3" } -- b / db
             local tlcolor     = { "startcolor", "trace:4" } -- y / dy
             for unicode, character in next, characters do
-                local mathkern = character.mathkern
-                local italic   = character.vitalic or character.italic
-                if mathkern or (italic and italic ~= 0) then
+                local mathkerns = character.mathkerns
+                local italic    = character.vitalic or character.italic
+                if mathkerns or (italic and italic ~= 0) then
                     local width  = character.width  or 0
                     local height = character.height or 0
                     local depth  = character.depth  or 0
@@ -206,11 +206,11 @@ local function initialize(tfmdata,key,value)
                         count = count + 1 list[count] = pop
                         count = count + 1 list[count] = black
                     end
-                    if mathkern then
-                        local br = mathkern.bottomright
-                        local tr = mathkern.topright
-                        local bl = mathkern.bottomleft
-                        local tl = mathkern.topleft
+                    if mathkerns then
+                        local br = mathkerns.bottomright
+                        local tr = mathkerns.topright
+                        local bl = mathkerns.bottomleft
+                        local tl = mathkerns.topleft
                         if br then
                             local done = false
                             for i=1,#br do
diff --git a/tex/context/base/mkxl/math-act.lmt b/tex/context/base/mkxl/math-act.lmt
index 047a5cbc6..19464b522 100644
--- a/tex/context/base/mkxl/math-act.lmt
+++ b/tex/context/base/mkxl/math-act.lmt
@@ -134,35 +134,27 @@ function mathematics.checkaccentbaseheight(target,original)
     end
 end
 
-function mathematics.checkprivateparameters(target,original)
-    local mathparameters = target.mathparameters
-    if mathparameters then
-        local parameters = target.parameters
-        local properties = target.properties
-        if parameters then
-            local size = parameters.size
-            if size then
---                 if not mathparameters.FractionDelimiterSize then
---                     mathparameters.FractionDelimiterSize = 1.01 * size
---                 end
---                 if not mathparameters.FractionDelimiterDisplayStyleSize then
---                     mathparameters.FractionDelimiterDisplayStyleSize = 2.40 * size
---                 end
---                 if not mathparameters.PrimeSuperscriptSpace then
---                     mathparameters.PrimeSuperscriptSpace = size / 20
---                 end
-            elseif properties then
-                report_math("invalid parameters in font %a",properties.fullname or "?")
-            else
-                report_math("invalid parameters in font")
-            end
-        elseif properties then
-            report_math("no parameters in font %a",properties.fullname or "?")
-        else
-            report_math("no parameters and properties in font")
-        end
-    end
-end
+-- function mathematics.checkprivateparameters(target,original)
+--     local mathparameters = target.mathparameters
+--     if mathparameters then
+--         local parameters = target.parameters
+--         local properties = target.properties
+--         if parameters then
+--             local size = parameters.size
+--             if size then
+--                 -- gone
+--             elseif properties then
+--                 report_math("invalid parameters in font %a",properties.fullname or "?")
+--             else
+--                 report_math("invalid parameters in font")
+--             end
+--         elseif properties then
+--             report_math("no parameters in font %a",properties.fullname or "?")
+--         else
+--             report_math("no parameters and properties in font")
+--         end
+--     end
+-- end
 
 function mathematics.overloadparameters(target,original)
     local mathparameters = target.mathparameters
@@ -692,6 +684,33 @@ end
 
 do
 
+    -- musical timestamp: March 2022, Antonio Sanches (Bad Hombre), live performance in NL
+
+    function mathtweaks.kerns(target,original,parameters)
+        local kerns = parameters.list
+        if kerns then
+            local characters = target.characters
+            local function kernone(unicode,data)
+                local chardata = characters[unicode]
+                local height = chardata.height or 0
+                local depth  = chardata.depth  or 0
+                local width  = chardata.width  or 0
+                local k = data.topleft     ; if k and k ~= 0 then chardata.topleft     = k * width end
+                local k = data.topright    ; if k and k ~= 0 then chardata.topright    = k * width end
+                local k = data.bottomleft  ; if k and k ~= 0 then chardata.bottomleft  = k * width end
+                local k = data.bottomright ; if k and k ~= 0 then chardata.bottomright = k * width end
+            end
+            for unicode, data in next, kerns do
+                kernone(unicode,data) -- withscriptcode(tfmdata,unicode,data,kernone)
+                -- also smaller
+            end
+        end
+    end
+
+end
+
+do
+
  -- local list = {
  --     [0x203E] = { factor = .4 }, -- overbar
  --     [0x203E] = { factor = .7 }, -- underbar
@@ -1042,6 +1061,29 @@ end
 
 do
 
+    local list = { 0x2061, 0x2062, 0x2063, 0x2064 }
+
+    function mathtweaks.wipecues(target,original,parameters)
+        local characters = target.characters
+        local tobewiped  = parameters.list or list
+        for i=1,#tobewiped do
+            local unicode = tobewiped[i]
+            characters[unicode] = {
+                width   = 0,
+                height  = 0,
+                depth   = 0,
+                unicode = unicode,
+            }
+            if trace_tweaking then
+                report_tweak("character %U has been wiped",unicode)
+            end
+        end
+    end
+
+end
+
+do
+
     -- For Ton, who needs the high minus and plus for calculator signs in Dutch
     -- school math books.
 
@@ -1213,7 +1255,7 @@ end
 sequencers.appendaction("mathparameters","system","mathematics.overloadparameters")
 sequencers.appendaction("mathparameters","system","mathematics.scaleparameters")
 sequencers.appendaction("mathparameters","system","mathematics.checkaccentbaseheight")  -- should go in lfg instead
-sequencers.appendaction("mathparameters","system","mathematics.checkprivateparameters") -- after scaling !
+----------.appendaction("mathparameters","system","mathematics.checkprivateparameters") -- after scaling !
 
 sequencers.appendaction("beforecopyingcharacters","system","mathematics.tweakbeforecopyingfont")
 sequencers.appendaction("aftercopyingcharacters", "system","mathematics.tweakaftercopyingfont")
diff --git a/tex/context/base/mkxl/math-ali.mkxl b/tex/context/base/mkxl/math-ali.mkxl
index 7329fed96..cc3e363db 100644
--- a/tex/context/base/mkxl/math-ali.mkxl
+++ b/tex/context/base/mkxl/math-ali.mkxl
@@ -823,8 +823,10 @@
    \fi
    \push_macro_c_math_cases_nc
    \mathatom \s!class \mathwrappedcode \bgroup
+   \scratchdimen\mathcasesparameter\c!leftmargin\relax
+   \ifzeropt\scratchdimen\else\kern\scratchdimen\fi
    \mathcasesparameter\c!left
-  %\startmathfenced[\mathcasesparameter\c!somekey]%
+   \math_fenced_start_wrap{\mathcasesparameter\c!fences}%
    \mathatom \s!class \mathconstructcode \bgroup
    \vcenter\bgroup
    \enforced\let\MC\math_cases_NC
@@ -857,8 +859,10 @@
    \egroup
    \egroup
    \egroup
-  %\stopmathfenced
-   \mathcasesparameter\c!right
+   \math_fenced_stop_wrap
+   \mathcasesparameter\c!right\relax
+   \scratchdimen\mathcasesparameter\c!rightmargin\relax
+   \ifzeropt\scratchdimen\else\kern\scratchdimen\fi
    \egroup
    \pop_macro_c_math_cases_nc
    \endgroup}
@@ -873,13 +877,15 @@
 
 \setupmathcases
 % [cases]
-  [\c!left={\startmathfenced[cases]},
-   \c!right=\stopmathfenced]
+  [\c!leftmargin=\zeropoint,
+   \c!rightmargin=\zeropoint,
+   \c!left=,
+   \c!right=,
+   \c!fences=cases]
 
 \definemathcases
   [sesac]
-  [\c!left={\startmathfenced[sesac]},
-   \c!right=\stopmathfenced]
+  [\c!fences=sesac]
 
 %D \startbuffer
 %D \placeformula \startformula \startcases
@@ -934,9 +940,12 @@
 
 \setupmathmatrix
   [\c!distance=\emwidth,
+   \c!fences=,
    \c!left=,
    \c!right=,
    \c!align=\v!middle,
+   \c!leftmargin=\zeropoint,
+   \c!rightmargin=\zeropoint,
    \c!rulecolor=,
    \c!rulethickness=\linewidth]
 
@@ -968,13 +977,27 @@
    \dostoptagged
    \endlocalcontrol}
 
+% \protected\def\math_matrix_start_cell
+%   {\dostarttagged\t!mtablecell\empty
+%    \hss
+%    \math_left_of_eqalign
+%    \startimath
+%    \math_matrix_set_style
+%    \tabskip\zeropoint
+%    \everycr\emptytoks}
+%
+% \protected\def\math_matrix_stop_cell
+%   {\stopimath
+%    \math_right_of_eqalign
+%    \hss
+%    \dostoptagged}
+
 \protected\def\math_matrix_start_cell
   {\dostarttagged\t!mtablecell\empty
    \hss
    \math_left_of_eqalign
    \startimath
    \math_matrix_set_style
-   \tabskip\zeropoint
    \everycr\emptytoks}
 
 \protected\def\math_matrix_stop_cell
@@ -995,73 +1018,140 @@
 
 % \c_math_matrix_anchor_mode3
 
+% this will be replaced
+
+%\permanent\protected\def\setmathmatrixanchoring[#1]%
+%  {\c_math_matrix_anchor_mode\zerocount
+%   \processaction
+%     [#1]
+%     [    \v!left=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone+\plustwo\relax,
+%         \v!right=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone+\plusfour\relax,
+%          \v!both=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone+\plustwo+\plusfour\relax,
+%           \v!yes=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone]}
+%
+%\def\math_matrix_anchor
+%  {\ifbitwiseand\c_math_matrix_anchor_mode\plusone
+%     \markanchor{matrix}{\numexpr\c_math_eqalign_column+1\relax}\c_math_eqalign_row
+%   \fi}
+%
+%\protected\def\math_matrix_distance
+%  {\relax
+%   \ifdim\d_math_eqalign_distance>\zeropoint
+%     \hskip.5\d_math_eqalign_distance
+%   \fi
+%   \math_matrix_anchor
+%   \ifdim\d_math_eqalign_distance>\zeropoint
+%     \hskip.5\d_math_eqalign_distance
+%   \fi
+%   \relax}
+%
+%\protected\def\math_matrix_distance_first
+%  {\relax
+%   \ifbitwiseand\c_math_matrix_anchor_mode\plusone
+%     \math_matrix_anchor
+%   \fi
+%   \ifdim\d_math_eqalign_distance>\zeropoint
+%     \ifbitwiseand\c_math_matrix_anchor_mode\plustwo
+%       \hskip.5\d_math_eqalign_distance
+%     \fi
+%   \fi
+%   \relax}
+%
+%\protected\def\math_matrix_distance_last
+%  {\relax
+%   \ifdim\d_math_eqalign_distance>\zeropoint
+%     \ifbitwiseand\c_math_matrix_anchor_mode\plusfour
+%       \hskip.5\d_math_eqalign_distance
+%     \fi
+%   \fi
+%   \ifbitwiseand\c_math_matrix_anchor_mode\plusone
+%     \math_matrix_anchor
+%   \fi
+%   \relax}
+%
+% \def\math_matrix_preamble
+%   {\math_matrix_strut
+%    \math_matrix_distance_first
+%    \global\advance\c_math_eqalign_column\plusone
+%    \math_matrix_start_cell
+%      \aligncontent
+%    \math_matrix_stop_cell
+%    \aligntab
+%    \aligntab
+%    \math_matrix_distance
+%    \global\advance\c_math_eqalign_column\plusone
+%    \math_matrix_start_cell
+%      \aligncontent
+%    \math_matrix_stop_cell}
+%
+% \permanent\protected\def\math_matrix_NR
+%   {\aligntab\omit
+%    \math_matrix_distance_last
+%    \math_matrix_stop_row
+%    \math_matrix_pickup
+%    \crcr
+%    \math_matrix_start_row}
+%
+% \permanent\protected\def\math_matrix_NC
+%   {\ifconditional\c_math_matrix_first
+%      \expandafter\math_matrix_NC_yes
+%    \else
+%      \expandafter\math_matrix_NC_nop
+%    \fi}
+
 \permanent\protected\def\setmathmatrixanchoring[#1]%
   {\c_math_matrix_anchor_mode\zerocount
    \processaction
-     [#1]
-     [    \v!left=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone+\plustwo\relax,
-         \v!right=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone+\plusfour\relax,
-          \v!both=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone+\plustwo+\plusfour\relax,
-           \v!yes=>\bitwiseflip\c_math_matrix_anchor_mode\numexpr\plusone]}
+     [#1]%
+     [\v!both=>\c_math_matrix_anchor_mode\plusone,%
+       \v!yes=>\c_math_matrix_anchor_mode\plusone]}
 
 \def\math_matrix_anchor
-  {\ifbitwiseand\c_math_matrix_anchor_mode\plusone
+  {\ifcase\c_math_matrix_anchor_mode\else
      \markanchor{matrix}{\numexpr\c_math_eqalign_column+1\relax}\c_math_eqalign_row
    \fi}
 
-\protected\def\math_matrix_distance
+\protected\def\math_matrix_anchor_first
   {\relax
-   \ifdim\d_math_eqalign_distance>\zeropoint
-     \hskip.5\d_math_eqalign_distance
-   \fi
-   \math_matrix_anchor
-   \ifdim\d_math_eqalign_distance>\zeropoint
-     \hskip.5\d_math_eqalign_distance
-   \fi
-   \relax}
-
-\protected\def\math_matrix_distance_first
-  {\relax
-   \ifbitwiseand\c_math_matrix_anchor_mode\plusone
+   \ifcase\c_math_matrix_anchor_mode\else
      \math_matrix_anchor
-   \fi
-   \ifdim\d_math_eqalign_distance>\zeropoint
-     \ifbitwiseand\c_math_matrix_anchor_mode\plustwo
-       \hskip.5\d_math_eqalign_distance
-     \fi
-   \fi
-   \relax}
+   % \ifdim\d_math_eqalign_distance>\zeropoint
+   %   \ifbitwiseand\c_math_matrix_anchor_mode\plustwo
+   %      \hskip.5\d_math_eqalign_distance
+   %   \fi
+   % \fi
+   \fi}
 
-\protected\def\math_matrix_distance_last
+\protected\def\math_matrix_anchor_last
   {\relax
-   \ifdim\d_math_eqalign_distance>\zeropoint
-     \ifbitwiseand\c_math_matrix_anchor_mode\plusfour
-       \hskip.5\d_math_eqalign_distance
-     \fi
-   \fi
-   \ifbitwiseand\c_math_matrix_anchor_mode\plusone
+   \ifcase\c_math_matrix_anchor_mode\else
+   % \ifdim\d_math_eqalign_distance>\zeropoint
+   %   \ifbitwiseand\c_math_matrix_anchor_mode\plusfour
+   %     \hskip.5\d_math_eqalign_distance
+   %   \fi
+   % \fi
      \math_matrix_anchor
-   \fi
-   \relax}
+   \fi}
 
 \def\math_matrix_preamble
   {\math_matrix_strut
-   \math_matrix_distance_first
+   \math_matrix_anchor_first
    \global\advance\c_math_eqalign_column\plusone
    \math_matrix_start_cell
      \aligncontent
    \math_matrix_stop_cell
    \aligntab
    \aligntab
-   \math_matrix_distance
+   \math_matrix_anchor
+   \aligncontent
+   \aligntab
    \global\advance\c_math_eqalign_column\plusone
    \math_matrix_start_cell
      \aligncontent
    \math_matrix_stop_cell}
 
 \permanent\protected\def\math_matrix_NR
-  {\aligntab\omit
-   \math_matrix_distance_last
+  {\math_matrix_anchor_last
    \math_matrix_stop_row
    \math_matrix_pickup
    \crcr
@@ -1076,7 +1166,9 @@
 
 \permanent\protected\def\math_matrix_pickup{\global\settrue \c_math_matrix_first}
 \permanent\protected\def\math_matrix_NC_yes{\global\setfalse\c_math_matrix_first}
-\permanent\protected\def\math_matrix_NC_nop{\aligntab} % avoids lookahead
+%permanent\protected\def\math_matrix_NC_nop{\aligntab} % avoids lookahead
+\permanent\protected\def\math_matrix_NC_nop{\aligntab\aligntab} % avoids lookahead
+
 
 \def\math_matrix_check_rule_step#1%
   {\doifelsenumber{#1}
@@ -1121,6 +1213,39 @@
    \enforced\let\TB\math_common_TB
 \to \everymathmatrix
 
+% \def\math_matrix_start_processing
+%   {\ifmmode
+%      \mathatom \s!class \mathwrappedcode
+%    \else
+%      \dontleavehmode
+%    \fi
+%    \bgroup
+%    \tabskip\zeropoint
+%    \math_matrix_pickup
+%    \the\everymathmatrix
+%    %
+%  % \enforced\let\endmath\relax
+%    %
+%    \setbox\nextbox\vbox\bgroup
+%    \math_matrix_start_table
+%    \halign \bgroup
+%      % preamble
+%      \span\math_matrix_preamble
+%      % done
+%      \crcr
+%      \math_matrix_start_row}
+%
+% \def\math_matrix_stop_processing
+%   {%\math_matrix_stop_wrapup % optional
+%    \math_matrix_stop_row
+%    \egroup
+%    \math_matrix_stop_table
+%    \egroup
+%    \mathmatrixleft  % experimental hook
+%    \math_matrix_finish_nextbox
+%    \mathmatrixright % experimental hook
+%    \egroup}
+
 \def\math_matrix_start_processing
   {\ifmmode
      \mathatom \s!class \mathwrappedcode
@@ -1128,7 +1253,7 @@
      \dontleavehmode
    \fi
    \bgroup
-   \tabskip\zeropoint
+   \tabskip.5\d_math_eqalign_distance
    \math_matrix_pickup
    \the\everymathmatrix
    %
@@ -1223,9 +1348,15 @@
    \begincsname\??mathmatrixalignlocation\mathmatrixparameter\c!location\endcsname\hbox\bgroup
      \normalstartimath
      \Ustyle\scratchcounter
-     \mathmatrixparameter\c!left
+     \scratchdimen\mathmatrixparameter\c!leftmargin\relax
+     \ifzeropt\scratchdimen\else\kern\scratchdimen\fi
+     \mathmatrixparameter\c!left\relax
+     \math_fenced_start_wrap{\mathmatrixparameter\c!fences}%
      \mathatom \s!class \mathconstructcode {\vcenter{\box\nextbox}}% \was \vcenter
-     \mathmatrixparameter\c!right
+     \math_fenced_stop_wrap
+     \mathmatrixparameter\c!right\relax
+     \scratchdimen\mathmatrixparameter\c!rightmargin\relax
+     \ifzeropt\scratchdimen\else\kern\scratchdimen\fi
      \normalstopimath
    \egroup}
 
@@ -1420,29 +1551,28 @@
 
 \definemathmatrix
   [matrix:brackets]
-  [\c!left={\startmathfenced[bracket]},
-   \c!right=\stopmathfenced,
+  [\c!fences=bracket,
    \c!align=\v!middle]
 
 \definemathmatrix
   [matrix:parentheses]
-  [\c!left={\startmathfenced[parenthesis]},
-   \c!right=\stopmathfenced,
+  [\c!fences=parenthesis,
    \c!align=\v!middle]
 
 \definemathmatrix
   [matrix:bars]
-  [\c!left={\startmathfenced[bar]},
-   \c!right=\stopmathfenced,
+  [\c!fences=bar,
    \c!align=\v!middle]
 
 \definemathmatrix
   [matrix:braces]
-  [\c!left={\startmathfenced[brace]},
-   \c!right=\stopmathfenced,
+  [\c!fences=brace,
    \c!align=\v!middle]
 
-\definemathmatrix[thematrix][matrix:parentheses][\c!simplecommand=thematrix]
+\definemathmatrix
+  [thematrix]
+  [matrix:parentheses]
+  [\c!simplecommand=thematrix]
 
 %D \startbuffer
 %D \startformula
@@ -1464,6 +1594,30 @@
 %D
 %D \typebuffer \getbuffer
 
+%D Mikael needed this matrix in one of his advanced math courses that ran begin april 2022
+%D where new concepts were introduced:
+
+% \definemathfence
+%   [tekcarb]
+%   [\c!left="005D,\c!right="005B]
+
+\definemathmatrix
+  [xıɹʇɐɯ]
+  [\c!fences=tekcarb]
+
+%D Fortunately we were read for it:
+%D
+%D \startbuffer
+%D \startformula
+%D \startxıɹʇɐɯ
+%D   \NC a_1 \NC b_1 \NC c_1 \NR
+%D   \NC a_2 \NC b_2 \NC c_2 \NR
+%D \stopxıɹʇɐɯ
+%D \stopformula
+%D \stopbuffer
+%D
+%D \typebuffer \getbuffer
+
 %D \macros
 %D   {startintertext}
 %D
@@ -1567,61 +1721,77 @@
 %    \endgroup
 %    \normalbordermatrix}
 
+% %D \macros{overset, underset}
+% %D
+% %D The macros \type{\overset} and \type{\underset} are provided by
+% %D \AMS\ packages in \LATEX. These macro allows you to place a symbol
+% %D above or below another symbol, irrespective of whether the other
+% %D symbol is a relation or something else, and without influencing the
+% %D spacing.  For most cases there is a better way to do such things
+% %D (declaring a math command with limop option, or using accents), but
+% %D occasionally these macros can be useful, for example:
+% %D
+% %D \startbuffer
+% %D \startformula
+% %D \overset{*}{X} \underset{*}{X}
+% %D \stopformula
+% %D \stopbuffer
+% %D \typebuffer \getbuffer
+% %D
+% %D Use these macros sparingly. Remember, \TEX\ was designed for
+% %D mathematics, so there is usually a proper method for typesetting
+% %D common math notation.
+% %D
+% %D These macros are a cleaner version of \type {\binrel@} and
+% %D \type {\binrel@@} macros in \AMSTEX\ packages.
+%
+% \def\math_binrel_apply#1%
+%   {\begingroup
+%    \setbox\scratchbox\hbox
+%      {\thinmuskip   0mu
+%       \medmuskip   -1mu
+%       \thickmuskip -1mu
+%       \setbox\scratchbox\hbox{\normalstartimath#1\mathsurround\zeropoint\normalstopimath}%
+%       \kern-\wd\scratchbox
+%       \normalstartimath{}#1{}\mathsurround\zeropoint\normalstopimath}%
+%    \ifdim\wd\scratchbox<\zeropoint
+%      \endgroup
+%      \expandafter\mathbin
+%    \orelse\ifdim\wd\scratchbox>\zeropoint
+%      \endgroup
+%      \doubleexpandafter\mathrel
+%    \else
+%      \endgroup
+%      \doubleexpandafter\firstofoneargument
+%    \fi}
+%
+% \permanent\protected\def\overset#1#2%
+%   {\math_binrel_apply{#2}{\mathop{\kern\zeropoint#2}\limits\normalsuperscript{#1}}}
+%
+% \permanent\protected\def\underset#1#2%
+%   {\math_binrel_apply{#2}{\mathop{\kern\zeropoint#2}\limits\normalsubscript  {#1}}}
+
 %D \macros{overset, underset}
 %D
-%D The macros \type{\overset} and \type{\underset} are provided by
-%D \AMS\ packages in \LATEX. These macro allows you to place a symbol
-%D above or below another symbol, irrespective of whether the other
-%D symbol is a relation or something else, and without influencing the
-%D spacing.  For most cases there is a better way to do such things
-%D (declaring a math command with limop option, or using accents), but
-%D occasionally these macros can be useful, for example:
+%D The macros \type {\overset} and \type {\underset} are provided by \AMS\ packages
+%D in \LATEX. These macro allows you to place a symbol above or below another
+%D symbol, irrespective of whether the other symbol is a relation or something else,
+%D and without influencing the spacing. Because in \LUAMETATEX\ we're less limited,
+%D we have rather simple definitions compared to \MKIV. One cna also do:
 %D
-%D \startbuffer
-%D \startformula
-%D \overset{*}{X} \underset{*}{X}
-%D \stopformula
-%D \stopbuffer
-%D \typebuffer \getbuffer
-%D
-%D Use these macros sparingly. Remember, \TEX\ was designed for
-%D mathematics, so there is usually a proper method for typesetting
-%D common math notation.
-%D
-%D These macros are a cleaner version of \type {\binrel@} and
-%D \type {\binrel@@} macros in \AMSTEX\ packages.
-
-\def\math_binrel_apply#1%
-  {\begingroup
-   \setbox\scratchbox\hbox
-     {\thinmuskip   0mu
-      \medmuskip   -1mu
-      \thickmuskip -1mu
-      \setbox\scratchbox\hbox{\normalstartimath#1\mathsurround\zeropoint\normalstopimath}%
-      \kern-\wd\scratchbox
-      \normalstartimath{}#1{}\mathsurround\zeropoint\normalstopimath}%
-   \ifdim\wd\scratchbox<\zeropoint
-     \endgroup
-     \expandafter\mathbin
-   \orelse\ifdim\wd\scratchbox>\zeropoint
-     \endgroup
-     \doubleexpandafter\mathrel
-   \else
-     \endgroup
-     \doubleexpandafter\firstofoneargument
-   \fi}
-
-\permanent\protected\def\overset#1#2%
-  {\math_binrel_apply{#2}{\mathop{\kern\zeropoint#2}\limits\normalsuperscript{#1}}}
+%D \starttyping
+%D $b\limits^a$
+%D $<\limits^a$
+%D \stoptyping
 
-\permanent\protected\def\underset#1#2%
-  {\math_binrel_apply{#2}{\mathop{\kern\zeropoint#2}\limits\normalsubscript  {#1}}}
+\permanent\protected\def\overset #1#2{#2\limits\normalsuperscript{#1}}
+\permanent\protected\def\underset#1#2{#2\limits\normalsubscript  {#1}}
 
 %D The following code comes from \type {math-str.mkiv}.
 %D
-%D Here we implement a basic math alignment mechanism. Numbers are also handled. The macros
-%D \type {\startinnermath} and \type {\stopinnermath} can be overloaded in specialized
-%D modules.
+%D Here we implement a basic math alignment mechanism. Numbers are also handled. The
+%D macros \type {\startinnermath} and \type {\stopinnermath} can be overloaded in
+%D specialized modules.
 
 \installcorenamespace{mathinnerstart}
 \installcorenamespace{mathinnerstop}
@@ -2166,6 +2336,10 @@
 
 \setupmathsimplealign
   [\c!distance=\v!math,
+   \c!leftmargin=\zeropoint,
+   \c!rightmargin=\zeropoint,
+   \c!left=,
+   \c!right=,
    \c!align=\v!all:\v!middle,
    \c!textdistance=.25\emwidth]
 
@@ -2187,9 +2361,17 @@
    \ifarguments\or\or
      \setupcurrentmathsimplealign[#2]%
    \fi
+   \edef\p_strut{\mathsimplealignparameter\c!strut}%
+   \ifx\p_strut\v!yes
+     \enforced\let\math_align_strut\strut
+   \else
+     \enforced\let\math_align_strut\relax
+   \fi
    \mathatom \s!class \mathwrappedcode \bgroup
-   \mathsimplealignparameter\c!left
-  %\startmathfenced[\mathsimplealignparameter\c!somekey]%
+   \scratchdimen\mathsimplealignparameter\c!leftmargin\relax
+   \ifzeropt\scratchdimen\else\kern\scratchdimen\fi
+   \mathsimplealignparameter\c!left\relax
+   \math_fenced_start_wrap{\mathsimplealignparameter\c!fences}%
    \mathatom \s!class \mathconstructcode \bgroup
    \vcenter\bgroup
    \enforced\let\MC\math_simplealign_NC
@@ -2211,6 +2393,7 @@
      \global\advance\c_math_eqalign_column\plusone
      \math_left_of_eqalign  % \hfil
      \ignorespaces
+     \math_align_strut
      \startimath
      \aligncontent
      \stopimath
@@ -2226,6 +2409,7 @@
        \kern\m_simplealign_distance
      \fi
      \ignorespaces
+     \math_align_strut
      \startimath
      \aligncontent
      \stopimath
@@ -2238,8 +2422,10 @@
    \egroup
    \egroup
    \egroup
-  %\stopmathfenced
-   \mathsimplealignparameter\c!right
+   \math_fenced_stop_wrap
+   \mathsimplealignparameter\c!right\relax
+   \scratchdimen\mathsimplealignparameter\c!rightmargin\relax
+   \ifzeropt\scratchdimen\else\kern\scratchdimen\fi
    \setbox\scratchbox\hbox{\mathsimplealignparameter\c!text}%
    \ifvoid\scratchbox\else
      \hskip\mathsimplealignparameter\c!textdistance
diff --git a/tex/context/base/mkxl/math-def.mkxl b/tex/context/base/mkxl/math-def.mkxl
index 53165a30c..6c434f995 100644
--- a/tex/context/base/mkxl/math-def.mkxl
+++ b/tex/context/base/mkxl/math-def.mkxl
@@ -28,50 +28,50 @@
 
 %D The \mfunction macro is an alternative for \hbox with a controlable font switch.
 
-\definemathcommand [arccos]  [nolop] {\mfunctionlabeltext{arccos}}
-\definemathcommand [arcsin]  [nolop] {\mfunctionlabeltext{arcsin}}
-\definemathcommand [arctan]  [nolop] {\mfunctionlabeltext{arctan}}
-\definemathcommand [arccosh] [nolop] {\mfunctionlabeltext{arccosh}}
-\definemathcommand [arcsinh] [nolop] {\mfunctionlabeltext{arcsinh}}
-\definemathcommand [arctanh] [nolop] {\mfunctionlabeltext{arctanh}}
-\definemathcommand [acos]    [nolop] {\mfunctionlabeltext{acos}}
-\definemathcommand [asin]    [nolop] {\mfunctionlabeltext{asin}}
-\definemathcommand [atan]    [nolop] {\mfunctionlabeltext{atan}}
-\definemathcommand [arg]     [nolop] {\mfunctionlabeltext{arg}}
-\definemathcommand [cosh]    [nolop] {\mfunctionlabeltext{cosh}}
-\definemathcommand [cos]     [nolop] {\mfunctionlabeltext{cos}}
-\definemathcommand [coth]    [nolop] {\mfunctionlabeltext{coth}}
-\definemathcommand [cot]     [nolop] {\mfunctionlabeltext{cot}}
-\definemathcommand [csc]     [nolop] {\mfunctionlabeltext{csc}}
-\definemathcommand [deg]     [nolop] {\mfunctionlabeltext{deg}}
-\definemathcommand [det]     [limop] {\mfunctionlabeltext{det}}
-\definemathcommand [dim]     [nolop] {\mfunctionlabeltext{dim}}
-\definemathcommand [exp]     [nolop] {\mfunctionlabeltext{exp}}
-\definemathcommand [gcd]     [limop] {\mfunctionlabeltext{gcd}}
-\definemathcommand [hom]     [nolop] {\mfunctionlabeltext{hom}}
-\definemathcommand [inf]     [limop] {\mfunctionlabeltext{inf}}
-\definemathcommand [injlim]  [limop] {\mfunctionlabeltext{injlim}}
-\definemathcommand [ker]     [nolop] {\mfunctionlabeltext{ker}}
-\definemathcommand [lg]      [nolop] {\mfunctionlabeltext{lg}}
-\definemathcommand [liminf]  [limop] {\mfunctionlabeltext{liminf}}
-\definemathcommand [limsup]  [limop] {\mfunctionlabeltext{limsup}}
-\definemathcommand [lim]     [limop] {\mfunctionlabeltext{lim}}
-\definemathcommand [ln]      [nolop] {\mfunctionlabeltext{ln}}
-\definemathcommand [log]     [nolop] {\mfunctionlabeltext{log}}
-\definemathcommand [median]  [limop] {\mfunctionlabeltext{median}}
-\definemathcommand [max]     [limop] {\mfunctionlabeltext{max}}
-\definemathcommand [min]     [limop] {\mfunctionlabeltext{min}}
-\definemathcommand [mod]     [limop] {\mfunctionlabeltext{mod}}
-%definemathcommand [div]     [limop] {\mfunctionlabeltext{div}}      % overloads \div symbol
-\definemathcommand [projlim] [limop] {\mfunctionlabeltext{projlim}}
-\definemathcommand [Pr]      [limop] {\mfunctionlabeltext{Pr}}
-\definemathcommand [sec]     [nolop] {\mfunctionlabeltext{sec}}
-\definemathcommand [sinh]    [nolop] {\mfunctionlabeltext{sinh}}
-\definemathcommand [sin]     [nolop] {\mfunctionlabeltext{sin}}
-\definemathcommand [sup]     [limop] {\mfunctionlabeltext{sup}}
-\definemathcommand [tanh]    [nolop] {\mfunctionlabeltext{tanh}}
-\definemathcommand [tan]     [nolop] {\mfunctionlabeltext{tan}}
-\definemathcommand [diff]            {\mfunctionlabeltext{diff}}
+\definemathfunction [arccos]
+\definemathfunction [arcsin]
+\definemathfunction [arctan]
+\definemathfunction [arccosh]
+\definemathfunction [arcsinh]
+\definemathfunction [arctanh]
+\definemathfunction [acos]
+\definemathfunction [asin]
+\definemathfunction [atan]
+\definemathfunction [arg]
+\definemathfunction [cosh]
+\definemathfunction [cos]
+\definemathfunction [coth]
+\definemathfunction [cot]
+\definemathfunction [csc]
+\definemathfunction [deg]
+\definemathfunction [det]     [\c!mathlimits=\v!yes]
+\definemathfunction [dim]
+\definemathfunction [exp]
+\definemathfunction [gcd]     [\c!mathlimits=\v!yes]
+\definemathfunction [hom]
+\definemathfunction [inf]     [\c!mathlimits=\v!yes]
+\definemathfunction [injlim]  [\c!mathlimits=\v!yes]
+\definemathfunction [ker]
+\definemathfunction [lg]
+\definemathfunction [liminf]  [\c!mathlimits=\v!yes]
+\definemathfunction [limsup]  [\c!mathlimits=\v!yes]
+\definemathfunction [lim]     [\c!mathlimits=\v!yes]
+\definemathfunction [ln]
+\definemathfunction [log]
+\definemathfunction [median]  [\c!mathlimits=\v!yes]
+\definemathfunction [max]     [\c!mathlimits=\v!yes]
+\definemathfunction [min]     [\c!mathlimits=\v!yes]
+\definemathfunction [mod]     [\c!mathlimits=\v!yes]
+%definemathfunction [div]     [\c!mathlimits=\v!yes]
+\definemathfunction [projlim] [\c!mathlimits=\v!yes]
+\definemathfunction [Pr]      [\c!mathlimits=\v!yes]
+\definemathfunction [sec]
+\definemathfunction [sinh]
+\definemathfunction [sin]
+\definemathfunction [sup]     [\c!mathlimits=\v!yes]
+\definemathfunction [tanh]
+\definemathfunction [tan]
+\definemathfunction [diff]
 
 \aliased\let\normalmatharg\arg % todo: maybe automatically
 
@@ -138,28 +138,28 @@
 
 \pushoverloadmode
 
-\definemathcommand [colonsep]               {\mkern-1.2mu}
-\definemathcommand [doublecolonsep]         {\mkern-0.9mu}
-
-\definemathcommand [centercolon]      [rel] {\mathstylevcenteredhbox\colon}
-\definemathcommand [colonminus]       [rel] {\centercolon\colonsep\mathrel{-}}
-%definemathcommand [minuscolon]       [rel] {\mathrel{-}\colonsep\centercolon} % native char
-%definemathcommand [colonequals]      [rel] {\centercolon\colonsep=}           % native char
-%definemathcommand [equalscolon]      [rel] {=\centercolon\colonsep}           % native char
-\definemathcommand [colonapprox]      [rel] {\centercolon\colonsep\approx}
-\definemathcommand [approxcolon]      [rel] {\approx\centercolon\colonsep}
-\definemathcommand [colonsim]         [rel] {\centercolon\colonsep\sim}
-\definemathcommand [simcolon]         [rel] {\sim\centercolon\colonsep}
-
-\definemathcommand [coloncolon]       [rel] {\centercolon\doublecolonsep\centercolon}
-\definemathcommand [coloncolonminus]  [rel] {\coloncolon\colonsep\mathrel{-}}
-\definemathcommand [minuscoloncolon]  [rel] {\mathrel{-}\colonsep\coloncolon}
-\definemathcommand [coloncolonequals] [rel] {\coloncolon\colonsep=}            % native char
-\definemathcommand [equalscoloncolon] [rel] {=\coloncolon\colonsep}
-\definemathcommand [coloncolonapprox] [rel] {\coloncolon\colonsep\approx}
-\definemathcommand [approxcoloncolon] [rel] {\approx\coloncolon\colonsep}
-\definemathcommand [coloncolonsim]    [rel] {\coloncolon\colonsep\sim}
-\definemathcommand [simcoloncolon]    [rel] {\sim\coloncolon\colonsep}
+\definemathcommand [colonsep]                       {\mkern-1.2mu}
+\definemathcommand [doublecolonsep]                 {\mkern-0.9mu}
+
+\definemathcommand [centercolon]      [\s!relation] {\mathstylevcenteredhbox\colon}
+\definemathcommand [colonminus]       [\s!relation] {\centercolon\colonsep\mathrel{-}}
+%definemathcommand [minuscolon]       [\s!relation] {\mathrel{-}\colonsep\centercolon} % native char
+%definemathcommand [colonequals]      [\s!relation] {\centercolon\colonsep=}           % native char
+%definemathcommand [equalscolon]      [\s!relation] {=\centercolon\colonsep}           % native char
+\definemathcommand [colonapprox]      [\s!relation] {\centercolon\colonsep\approx}
+\definemathcommand [approxcolon]      [\s!relation] {\approx\centercolon\colonsep}
+\definemathcommand [colonsim]         [\s!relation] {\centercolon\colonsep\sim}
+\definemathcommand [simcolon]         [\s!relation] {\sim\centercolon\colonsep}
+
+\definemathcommand [coloncolon]       [\s!relation] {\centercolon\doublecolonsep\centercolon}
+\definemathcommand [coloncolonminus]  [\s!relation] {\coloncolon\colonsep\mathrel{-}}
+\definemathcommand [minuscoloncolon]  [\s!relation] {\mathrel{-}\colonsep\coloncolon}
+\definemathcommand [coloncolonequals] [\s!relation] {\coloncolon\colonsep=}            % native char
+\definemathcommand [equalscoloncolon] [\s!relation] {=\coloncolon\colonsep}
+\definemathcommand [coloncolonapprox] [\s!relation] {\coloncolon\colonsep\approx}
+\definemathcommand [approxcoloncolon] [\s!relation] {\approx\coloncolon\colonsep}
+\definemathcommand [coloncolonsim]    [\s!relation] {\coloncolon\colonsep\sim}
+\definemathcommand [simcoloncolon]    [\s!relation] {\sim\coloncolon\colonsep}
 
 \popoverloadmode
 
diff --git a/tex/context/base/mkxl/math-fen.mkxl b/tex/context/base/mkxl/math-fen.mkxl
index bd51abe20..e1a648ba4 100644
--- a/tex/context/base/mkxl/math-fen.mkxl
+++ b/tex/context/base/mkxl/math-fen.mkxl
@@ -330,10 +330,24 @@
   {\math_fenced_fenced_stop\currentmathfence
    \endgroup}
 
+\def\math_fenced_start_wrap#1%
+  {\begingroup
+   \edef\m_math_fenced_wrap{#1}%
+   \ifempty\m_math_fenced_wrap \else
+     \math_fenced_fenced_start\m_math_fenced_wrap
+   \fi}
+
+\def\math_fenced_stop_wrap
+  {\ifempty\m_math_fenced_wrap \else
+     \math_fenced_fenced_stop\m_math_fenced_wrap
+   \fi
+   \endgroup}
+
 % cases are defined in math-ali:
 
-\definemathfence [cases] [\c!left="007B,\c!right=\v!none]
-\definemathfence [sesac] [\c!left=\v!none,\c!right="007D]
+\definemathfence [cases]   [\c!left="007B,\c!right=\v!none]
+\definemathfence [sesac]   [\c!left=\v!none,\c!right="007D]
+\definemathfence [tekcarb] [\c!left="005D,\c!right="005B]   % used for xıɹʇɐɯ
 
 %D This is new:
 %D
@@ -790,18 +804,18 @@
 \definemathcommand [bigg] {\choosemathbig3}
 \definemathcommand [Bigg] {\choosemathbig4}
 
-\definemathcommand [bigl]  [open]  [one] {\big}
-\definemathcommand [bigm]  [rel]   [one] {\big}
-\definemathcommand [bigr]  [close] [one] {\big}
-\definemathcommand [Bigl]  [open]  [one] {\Big}
-\definemathcommand [Bigm]  [rel]   [one] {\Big}
-\definemathcommand [Bigr]  [close] [one] {\Big}
-\definemathcommand [biggl] [open]  [one] {\bigg}
-\definemathcommand [biggm] [rel]   [one] {\bigg}
-\definemathcommand [biggr] [close] [one] {\bigg}
-\definemathcommand [Biggl] [open]  [one] {\Bigg}
-\definemathcommand [Biggm] [rel]   [one] {\Bigg}
-\definemathcommand [Biggr] [close] [one] {\Bigg}
+\definemathcommand [bigl]  [\s!open]     [one] {\big}
+\definemathcommand [bigm]  [\s!relation] [one] {\big}
+\definemathcommand [bigr]  [\s!close]    [one] {\big}
+\definemathcommand [Bigl]  [\s!open]     [one] {\Big}
+\definemathcommand [Bigm]  [\s!relation] [one] {\Big}
+\definemathcommand [Bigr]  [\s!close]    [one] {\Big}
+\definemathcommand [biggl] [\s!open]     [one] {\bigg}
+\definemathcommand [biggm] [\s!relation] [one] {\bigg}
+\definemathcommand [biggr] [\s!close]    [one] {\bigg}
+\definemathcommand [Biggl] [\s!open]     [one] {\Bigg}
+\definemathcommand [Biggm] [\s!relation] [one] {\Bigg}
+\definemathcommand [Biggr] [\s!close]    [one] {\Bigg}
 
 % \definemathfence [integral] [\c!left="222B]
 %
diff --git a/tex/context/base/mkxl/math-frc.mkxl b/tex/context/base/mkxl/math-frc.mkxl
index 6e41ee71e..ab43299e0 100644
--- a/tex/context/base/mkxl/math-frc.mkxl
+++ b/tex/context/base/mkxl/math-frc.mkxl
@@ -18,11 +18,8 @@
 %D I need to check it all again as there was a bug in luatex with dimensions that could
 %D resulted in side effects that made me mess with spacing.
 
-\permanent\protected\def\topstrut{\vrule\s!width\zeropoint\s!height\strutht\s!depth\zeropoint\relax}
-\permanent\protected\def\botstrut{\vrule\s!width\zeropoint\s!height\zeropoint\s!depth\strutdp\relax}
-
-% \permanent\protected\def\mathtopstrut{\setbox\scratchbox\mathstylehbox{(}\vrule\s!width\zeropoint\s!height\ht\scratchbox\s!depth\zeropoint\relax}
-% \permanent\protected\def\mathbotstrut{\setbox\scratchbox\mathstylehbox{(}\vrule\s!width\zeropoint\s!height\zeropoint\s!depth\dp\scratchbox\relax}
+\permanent\protected\def\topstrut{\srule\s!width\zeropoint\s!height\strutht  \s!depth\zeropoint\relax}
+\permanent\protected\def\botstrut{\srule\s!width\zeropoint\s!height\zeropoint\s!depth\strutdp  \relax}
 
 %D This module is reimplemented in \MKIV\ style.
 
diff --git a/tex/context/base/mkxl/math-ini.mkxl b/tex/context/base/mkxl/math-ini.mkxl
index fceedb21e..b278ba1e8 100644
--- a/tex/context/base/mkxl/math-ini.mkxl
+++ b/tex/context/base/mkxl/math-ini.mkxl
@@ -14,10 +14,6 @@
 \writestatus{loading}{ConTeXt Math Macros / Initializations}
 
 % todo: hpack as we skip math anyway
-%
-% todo: 0x2061 : function application
-% todo: 0x2062 : invisible times
-% todo: 0x2063 : invisible comma
 
 % a bit tricky way to set ... no (pseudo) registers but math hash values:
 %
@@ -191,13 +187,25 @@
 \copymathspacing \mathexponentialcode  \mathordinarycode
 \copymathspacing \mathfunctioncode     \mathordinarycode
 \copymathspacing \mathdigitcode        \mathordinarycode
-
+\copymathspacing \mathfunctioncode     \mathoperatorcode
 \copymathspacing \mathconstructcode    \mathinnercode
 \copymathspacing \mathwrappedcode      \mathfractioncode
 
 \setnewconstant\mathlimopcode \plusone
 \setnewconstant\mathnolopcode \plusone
 
+% \m{m^2/x__3}
+
+\setmathoptions\mathdivisioncode\numexpr
+    \nopreslackclassoptioncode
+   +\nopostslackclassoptioncode
+   +\lefttopkernclassoptioncode
+ % +\righttopkernclassoptioncode
+ % +\leftbottomkernclassoptioncode
+   +\rightbottomkernclassoptioncode
+\relax
+
+
 % obsolete
 
 \setnewconstant\mathboxcode     \zerocount
@@ -1043,12 +1051,12 @@
 \permanent\protected\def\math_fraktur     {\setmathalphabet \s!fraktur   \setmathfontstylealternate\s!fraktur}
 \permanent\protected\def\math_blackboard  {\setmathalphabet \s!blackboard\setmathfontstylealternate\s!blackboard}
 
-\permanent\protected\def\mathupright     {\mathgroupedcommandcs\math_upright}
-\permanent\protected\def\mathitalic      {\mathgroupedcommandcs\math_italic}
-\permanent\protected\def\mathscript      {\mathgroupedcommandcs\math_script}
+\permanent\protected\def\mathupright     {\mathgroupedcommandcs\math_upright     }
+\permanent\protected\def\mathitalic      {\mathgroupedcommandcs\math_italic      }
+\permanent\protected\def\mathscript      {\mathgroupedcommandcs\math_script      }
 \permanent\protected\def\mathcalligraphic{\mathgroupedcommandcs\math_calligraphic}
-\permanent\protected\def\mathfraktur     {\mathgroupedcommandcs\math_fraktur}
-\permanent\protected\def\mathblackboard  {\mathgroupedcommandcs\math_blackboard}
+\permanent\protected\def\mathfraktur     {\mathgroupedcommandcs\math_fraktur     }
+\permanent\protected\def\mathblackboard  {\mathgroupedcommandcs\math_blackboard  }
 
 \permanent\protected\def\math_rm{\setmathattribute\s!rm\s!tf\setmathfontstylealternate\s!tf}
 \permanent\protected\def\math_ss{\setmathattribute\s!ss\s!tf\setmathfontstylealternate\s!tf}
@@ -1062,17 +1070,17 @@
 \permanent\protected\def\math_bs{\setmathfontstyle\s!bi\setmathfontstylealternate\s!bi} % no sl
 \permanent\protected\def\math_bi{\setmathfontstyle\s!bi\setmathfontstylealternate\s!bi}
 
-\permanent\protected\def\mathrm{\mathgroupedcommandcs\math_rm\relax}
-\permanent\protected\def\mathss{\mathgroupedcommandcs\math_ss\relax}
-\permanent\protected\def\mathtt{\mathgroupedcommandcs\math_tt\relax}
+\permanent\protected\def\mathrm{\mathgroupedcommandcs\math_rm} % \relax not needed
+\permanent\protected\def\mathss{\mathgroupedcommandcs\math_ss}
+\permanent\protected\def\mathtt{\mathgroupedcommandcs\math_tt}
 
-\permanent\protected\def\mathtf{\mathgroupedcommandcs\math_tf\relax}
-\permanent\protected\def\mathsl{\mathgroupedcommandcs\math_sl\relax}
-\permanent\protected\def\mathit{\mathgroupedcommandcs\math_it\relax}
+\permanent\protected\def\mathtf{\mathgroupedcommandcs\math_tf}
+\permanent\protected\def\mathsl{\mathgroupedcommandcs\math_sl}
+\permanent\protected\def\mathit{\mathgroupedcommandcs\math_it}
 
-\permanent\protected\def\mathbf{\mathgroupedcommandcs\math_bf\relax}
-\permanent\protected\def\mathbs{\mathgroupedcommandcs\math_bs\relax}
-\permanent\protected\def\mathbi{\mathgroupedcommandcs\math_bi\relax}
+\permanent\protected\def\mathbf{\mathgroupedcommandcs\math_bf}
+\permanent\protected\def\mathbs{\mathgroupedcommandcs\math_bs}
+\permanent\protected\def\mathbi{\mathgroupedcommandcs\math_bi}
 
 \aliased\let\math_default\math_italic
 \aliased\let\mathdefault \math_italic
@@ -1108,10 +1116,10 @@
 \permanent\protected\def\fraktur   {\ifmmode\expandafter\mathfraktur     \fi}
 \permanent\protected\def\gothic    {\ifmmode\expandafter\mathfraktur     \fi}
 
-\permanent\protected\def\mathcal {\mathgroupedcommandcs\math_calligraphic\relax}  % for AMS compatibility
-\permanent\protected\def\mathscr {\mathgroupedcommandcs\math_script      \relax}  % for AMS compatibility
-\permanent\protected\def\mathfrak{\mathgroupedcommandcs\math_fraktur     \relax}  % for AMS compatibility
-\permanent\protected\def\mathbb  {\mathgroupedcommandcs\math_blackboard  \relax}  % for AMS compatibility
+\aliased\let\mathcal \mathcalligraphic % for AMS compatibility
+\aliased\let\mathscr \mathscript       % for AMS compatibility
+\aliased\let\mathfrak\mathfraktur      % for AMS compatibility
+\aliased\let\mathbb  \mathblackboard   % for AMS compatibility
 
 \ifdefined\normaltf \else \permanent\let\normaltf\tf \fi \permanent\protected\def\tf{\ifmmode\expandafter\mathtf\else\expandafter\normaltf\fi}
 \ifdefined\normalbf \else \permanent\let\normalbf\bf \fi \permanent\protected\def\bf{\ifmmode\expandafter\mathbf\else\expandafter\normalbf\fi}
@@ -1204,8 +1212,6 @@
 
 %D Not used that much:
 
-\installcorenamespace{mathcodecommand}
-
 \permanent\protected\def\mathlimop#1{\normalmathop{#1}} %no \limits
 \permanent\protected\def\mathbox  #1{\dontleavehmode\hbox\Ustartmath\mathsurround\zeropoint#1\Ustopmath}
 \permanent\protected\def\mathnolop#1{\normalmathop{#1}\nolimits}
@@ -1216,30 +1222,68 @@
 \aliased\let\mathnothing\firstofoneunexpanded
 \aliased\let\mathalpha  \firstofoneunexpanded
 
-% todo 'frac' and 'rad'
+% \installcorenamespace {mathclasses}
+%
+% \letcsname\??mathclasses         ord\endcsname\normalmathord
+% \letcsname\??mathclasses          op\endcsname\normalmathop
+% \letcsname\??mathclasses         rel\endcsname\normalmathrel
+% \letcsname\??mathclasses         bin\endcsname\normalmathbin
+% \letcsname\??mathclasses       punct\endcsname\normalmathpunct
+%
+% \letcsname\??mathclasses            \endcsname\normalmathord
+% \letcsname\??mathclasses       inner\endcsname\normalmathinner
+% \letcsname\??mathclasses        open\endcsname\normalmathopen
+% \letcsname\??mathclasses       close\endcsname\normalmathclose
+% \letcsname\??mathclasses    ordinary\endcsname\normalmathord
+% \letcsname\??mathclasses    operator\endcsname\normalmathop
+% \letcsname\??mathclasses    relation\endcsname\normalmathrel
+% \letcsname\??mathclasses      binary\endcsname\normalmathbin
+% \letcsname\??mathclasses punctuation\endcsname\normalmathpunct
+% \letcsname\??mathclasses    fraction\endcsname\normalmathfrac
+% \letcsname\??mathclasses     radical\endcsname\normalmathrad
+
+%D We need only a subset because many classes are sort of special.
 
-% why not \aliased ?
+\installcorenamespace{mathcodecommand}
 
-\letcsname\??mathcodecommand      ord\endcsname\mathord
-\letcsname\??mathcodecommand       op\endcsname\mathop
-\letcsname\??mathcodecommand      bin\endcsname\mathbin
-\letcsname\??mathcodecommand      rel\endcsname\mathrel
-\letcsname\??mathcodecommand     open\endcsname\mathopen
-\letcsname\??mathcodecommand    close\endcsname\mathclose
-\letcsname\??mathcodecommand    punct\endcsname\mathpunct
-\letcsname\??mathcodecommand    inner\endcsname\mathinner % hm
-%letcsname\??mathcodecommand fraction\endcsname\mathnothing
-%letcsname\??mathcodecommand  radical\endcsname\mathnothing
-%letcsname\??mathcodecommand   middle\endcsname\mathnothing
-\letcsname\??mathcodecommand    limop\endcsname\mathlimop
-\letcsname\??mathcodecommand    nolop\endcsname\mathnolop
+% short:
 
-% obsolete
+\aliased\letcsname\??mathcodecommand         ord\endcsname\mathord
+\aliased\letcsname\??mathcodecommand          op\endcsname\mathop
+\aliased\letcsname\??mathcodecommand         rel\endcsname\mathrel
+\aliased\letcsname\??mathcodecommand         bin\endcsname\mathbin
+\aliased\letcsname\??mathcodecommand       punct\endcsname\mathpunct
 
-\letcsname\??mathcodecommand      box\endcsname\mathbox
-%letcsname\??mathcodecommand   choice\endcsname\mathnothing
-\letcsname\??mathcodecommand    alpha\endcsname\mathalpha % hm
-\letcsname\??mathcodecommand  nothing\endcsname\mathnothing
+% official:
+
+\aliased\letcsname\??mathcodecommand            \endcsname\normalmathord
+\aliased\letcsname\??mathcodecommand       inner\endcsname\normalmathinner
+\aliased\letcsname\??mathcodecommand        open\endcsname\normalmathopen
+\aliased\letcsname\??mathcodecommand       close\endcsname\normalmathclose
+\aliased\letcsname\??mathcodecommand    ordinary\endcsname\normalmathord
+\aliased\letcsname\??mathcodecommand    operator\endcsname\normalmathop
+\aliased\letcsname\??mathcodecommand    relation\endcsname\normalmathrel
+\aliased\letcsname\??mathcodecommand      binary\endcsname\normalmathbin
+\aliased\letcsname\??mathcodecommand punctuation\endcsname\normalmathpunct
+\aliased\letcsname\??mathcodecommand    fraction\endcsname\normalmathfrac
+\aliased\letcsname\??mathcodecommand     radical\endcsname\normalmathrad
+
+% special:
+
+\aliased\letcsname\??mathcodecommand       limop\endcsname\mathlimop
+\aliased\letcsname\??mathcodecommand       nolop\endcsname\mathnolop
+
+% obsolete:
+
+\aliased\letcsname\??mathcodecommand         box\endcsname\mathbox
+%aliased\letcsname\??mathcodecommand      choice\endcsname\mathnothing
+\aliased\letcsname\??mathcodecommand       alpha\endcsname\mathalpha % hm
+\aliased\letcsname\??mathcodecommand     nothing\endcsname\mathnothing
+
+% usage:
+
+\def\math_class_by_parameter       #1{\normalexpanded{\noexpand\math_class_by_parameter_indeed{#1\c!mathclass}}}
+\def\math_class_by_parameter_indeed#1{\csname\??mathcodecommand\ifcsname\??mathcodecommand#1\endcsname#1\fi\endcsname}
 
 \permanent          \def\mathcodenumber #1{\the\csname math#1code\endcsname}
 \permanent\protected\def\mathcodecommand#1{\csname\??mathcodecommand#1\endcsname}
@@ -1285,9 +1329,9 @@
 
 %D Let's define a few comands here:
 
-%definemathcommand [mathstrut]       {\vphantom{(}}
-%definemathcommand [joinrel]         {\mathrel{\mkern-3mu}}
-\definemathcommand [joinrel]   [rel] {\mkern-3mu}
+%definemathcommand [mathstrut]               {\vphantom{(}}
+%definemathcommand [joinrel]                 {\mathrel{\mkern-3mu}}
+\definemathcommand [joinrel]   [\s!relation] {\mkern-3mu}
 
 \immutable\chardef\c_math_strut"28
 
@@ -1452,6 +1496,14 @@
    \c!functionstyle=, % rm ss etc i.e. known alternatives, otherwise math
    \c!functioncolor=]
 
+% in char-def:
+%
+%
+% \Umathcode"2061 = \mathghostcode \zerocount "2061 % \applyfunction
+% \Umathcode"2062 = \mathghostcode \zerocount "2062 % \invisibletimes
+% \Umathcode"2063 = \mathghostcode \zerocount "2063 % \invisiblecomma
+% \Umathcode"2064 = \mathghostcode \zerocount "2063 % \invisibleplus
+
 % \protected\def\math_mfunction_styled
 %   {%\begingroup
 %    \usemathematicscolorparameter\c!functioncolor
@@ -1491,26 +1543,52 @@
 %      \hbox{\math_mfunction_styled{\mathlabeltext{#1}}}%
 %    \egroup}
 
-\def\math_function_handle#1#2%
-  {\begingroup
-   \usemathematicscolorparameter\c!functioncolor
-   \edef\p_functionstyle{\mathematicsparameter\c!functionstyle}%
-   \ifempty\p_functionstyle
-     \expandafter\math_upright
-   \orelse\ifcsname\??alternativestyle\p_functionstyle\endcsname
-     \expandafter\lastnamedcs
-   \else
-     \expandafter\p_functionstyle
-   \fi
-   \mathatom mathfont class \mathfunctioncode \bgroup
-     \math_tags_mfunctionlab{#2}\c_apply_function % maybe move this before mathatom
+% \def\math_function_handle#1#2%
+%   {\begingroup
+%    \usemathematicscolorparameter\c!functioncolor
+%    \edef\p_functionstyle{\mathematicsparameter\c!functionstyle}%
+%    \ifempty\p_functionstyle
+%      \expandafter\math_upright
+%    \orelse\ifcsname\??alternativestyle\p_functionstyle\endcsname
+%      \expandafter\lastnamedcs
+%    \else
+%      \expandafter\p_functionstyle
+%    \fi
+%    \mathatom mathfont class \mathfunctioncode \bgroup
+%      \math_tags_mfunctionlab{#2}\c_apply_function % maybe move this before mathatom
+%      #1{#2}% how to avoid going ord, we need something text with no spacing at all
+%    \egroup
+%    \endgroup}
+
+\protected\def\math_function_handle#1#2%
+  {\mathatom mathfont class \mathfunctioncode \bgroup % textfont
+     \math_tags_mfunctionlab{#2}\c_apply_function
+     \usemathematicscolorparameter\c!functioncolor
+     \edef\p_functionstyle{\mathematicsparameter\c!functionstyle}%
+     \ifempty\p_functionstyle
+       \expandafter\math_upright
+     \orelse\ifcsname\??alternativestyle\p_functionstyle\endcsname
+       \expandafter\lastnamedcs
+     \else
+       \expandafter\p_functionstyle
+     \fi
      #1{#2}%
-   \egroup
-   \endgroup}
+   \egroup}
 
 \permanent\protected\def\mfunction         {\math_function_handle\firstofoneargument}
 \permanent\protected\def\mfunctionlabeltext{\math_function_handle\mathlabeltext}
 
+\permanent\tolerant\protected\def\definemathfunction[#1]#*[#2]%
+  {\frozen\defcsname#1\endcsname{\math_function_handle_label{#1}{#2}}}
+
+\protected\def\math_function_handle_label#1#2% tag settings
+  {\begingroup
+   \getdummyparameters[\c!mathlimits=,#2]%
+   \math_function_handle\mathlabeltext{#1}%
+   \ifcstok{\dummyparameter\c!mathlimits}\v!yes\limits\fi
+   \endgroup}
+
+
 \let\math_tags_mfunctiontxt\gobbletwoarguments
 \let\math_tags_mfunctionlab\gobbletwoarguments
 
@@ -2498,6 +2576,8 @@
 %permanent\def\mathstyletrigger#1{\numexpr#1\relax}
 \permanent\let\mathstyletrigger   \firstofoneargument
 
+\def\triggeredmathstyle#1{\Ustyle\numexpr\number#1\relax} % expandable
+
 \permanent\def\triggeredmathstyleparameter#1% to bypass the relax
   {\ifcase\numexpr\normalmathstyle\relax
      #1\displaystyle             \or % 0
@@ -2688,32 +2768,38 @@
 
 % to be tested: {#1} but it could have side effects
 
-% \protected\def\mathstylehbox#1% sensitive for: a \over b => {a\over b} or \frac{a}{b}
-%   {\normalexpanded{\hbox\bgroup
-%      \startimath\triggermathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup}
-
 \permanent\protected\def\mathstylehbox#1#% sensitive for: a \over b => {a\over b} or \frac{a}{b}
   {\math_style_hbox{#1}}
 
 \protected\def\math_style_hbox#1#2% sensitive for: a \over b => {a\over b} or \frac{a}{b}
   {\normalexpanded{\hbox#1\bgroup
-     \startimath\triggermathstyle\normalmathstyle}\mathsurround\zeropoint#2\stopimath\egroup}
+     \startimath\triggeredmathstyle\normalmathstyle}\mathsurround\zeropoint#2\stopimath\egroup}
+
+% adaptive variant:
+%
+% \protected\def\math_style_hbox#1#2% sensitive for: a \over b => {a\over b} or \frac{a}{b}
+%   {\normalexpanded{\setbox\scratchbox\hbox#1\bgroup
+%   \mathbeginclass\lastrightclass
+%   \startimath\Ustyle\the\mathstyle\relax}%
+%      \mathsurround\zeropoint#2\stopimath\egroup
+%      \box\scratchbox
+%   \mathrightclass\lastrightclass   }
 
 \permanent\protected\def\mathstylevbox#1%
   {\normalexpanded{\vbox\bgroup
-     \startimath\triggermathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup}
+     \startimath\triggeredmathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup}
 
 \permanent\protected\def\mathstylevcenter#1%
   {\normalexpanded{\vcenter\bgroup
-     \startimath\triggermathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup}
+     \startimath\triggeredmathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup}
 
 \permanent\protected\def\mathstylevcenteredhbox#1%
   {\normalexpanded{\vcenter\bgroup\hbox\bgroup
-     \startimath\triggermathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup\egroup}
+     \startimath\triggeredmathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup\egroup}
 
 \permanent\protected\def\mathstylevcenteredvbox#1%
   {\normalexpanded{\vcenter\bgroup\vbox\bgroup
-     \startimath\triggermathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup\egroup}
+     \startimath\triggeredmathstyle\normalmathstyle}\mathsurround\zeropoint#1\stopimath\egroup\egroup}
 
 \permanent\protected\def\setmathsmalltextbox#1#2#%
   {\normalizebodyfontsize\m_math_text_choice_face{\mathsmallstyleface\normalmathstyle}%
@@ -3286,7 +3372,7 @@
 
 \permanent\protected\def\smallmathsymbol#1%
   {\mathematics{\mathbin{\normalexpanded{\raise.15\exheight\hbox{\normalstartimath
-     \triggermathstyle{\the\numexpr\normalmathstyle+2\relax}#1%
+     \triggeredmathstyle{\the\numexpr\normalmathstyle+2\relax}#1%
    \normalstopimath}}}}}
 
 % this should be a primitive:
@@ -3773,8 +3859,6 @@
 \permanent\protected\def\setupmathspacing[#1]%
   {\begincsname\??mathspacing#1\endcsname}
 
-\installcorenamespace {mathclasses}
-
 % \defcsname\??mathspacing +\endcsname
 %   {\expandedloop\zerocount\plusseven\plusone
 %      {\Umathxscale
@@ -3796,31 +3880,6 @@
 % can become a lua call that globally defined it, then we can have
 % partials
 
-% todo: fences and stackers should be done the same: number or
-% name
-
-\letcsname\??mathclasses            \endcsname\normalmathord
-\letcsname\??mathclasses         ord\endcsname\normalmathord
-\letcsname\??mathclasses    ordinary\endcsname\normalmathord
-\letcsname\??mathclasses          op\endcsname\normalmathop
-\letcsname\??mathclasses    operator\endcsname\normalmathop
-\letcsname\??mathclasses         rel\endcsname\normalmathrel
-\letcsname\??mathclasses    relation\endcsname\normalmathrel
-\letcsname\??mathclasses         bin\endcsname\normalmathbin
-\letcsname\??mathclasses      binary\endcsname\normalmathbin
-\letcsname\??mathclasses       punct\endcsname\normalmathbin
-\letcsname\??mathclasses punctuation\endcsname\normalmathbin
-\letcsname\??mathclasses        frac\endcsname\normalmathfrac
-\letcsname\??mathclasses    fraction\endcsname\normalmathfrac
-\letcsname\??mathclasses         rad\endcsname\normalmathrad
-\letcsname\??mathclasses     radical\endcsname\normalmathrad
-
-\def\math_class_by_parameter#1%
-  {\normalexpanded{\noexpand\math_class_by_parameter_indeed{#1\c!mathclass}}}
-
-\def\math_class_by_parameter_indeed#1%
-  {\csname\??mathclasses\ifcsname\??mathclasses#1\endcsname#1\fi\endcsname}
-
 %D For now we define this here:
 
 \ifdefined\d \let\text_d\d \else \let\text_d\firstofoneargument \fi
diff --git a/tex/context/base/mkxl/math-noa.lmt b/tex/context/base/mkxl/math-noa.lmt
index 02f425542..11621f9bd 100644
--- a/tex/context/base/mkxl/math-noa.lmt
+++ b/tex/context/base/mkxl/math-noa.lmt
@@ -2121,7 +2121,7 @@ do
         name      = "setmathvariant",
         public    = true,
         protected = true,
-        arguments = "string",
+        arguments = "argument",
         actions   = mathematics.setvariant,
     }
 
diff --git a/tex/context/base/mkxl/math-pln.mkxl b/tex/context/base/mkxl/math-pln.mkxl
index 354f33a5f..ec64b7e4d 100644
--- a/tex/context/base/mkxl/math-pln.mkxl
+++ b/tex/context/base/mkxl/math-pln.mkxl
@@ -50,20 +50,20 @@
 \permanent\protected\def\buildrel#1\over#2%
   {\mathrel{\mathop{\kern\zeropoint#2}\limits^{#1}}}
 
-\permanent\protected\def\bmod
-  {\nonscript
-   \mskip-\medmuskip
-   \mkern5mu
-   \mfunction{mod}%
-   \penalty900
-   \mkern5mu
-   \nonscript
-   \mskip-\medmuskip}
-
-\permanent\protected\def\pmod#1%
-  {\allowbreak
-   \mkern18mu
-   (\mfunction{mod}\mskip\medmuskip#1)}
+    \permanent\protected\def\bmod
+      {\nonscript
+       \mskip-\medmuskip
+       \mkern5mu
+       \mfunction{mod}%
+       \penalty900
+       \mkern5mu
+       \nonscript
+       \mskip-\medmuskip}
+
+    \permanent\protected\def\pmod#1%
+      {\allowbreak
+       \mkern18mu
+       (\mfunction{mod}\mskip\medmuskip#1)}
 
 \permanent\protected\def\cases#1%
   {\left\{%
diff --git a/tex/context/base/mkxl/math-stc.mklx b/tex/context/base/mkxl/math-stc.mklx
index 970e1352d..86c6b6499 100644
--- a/tex/context/base/mkxl/math-stc.mklx
+++ b/tex/context/base/mkxl/math-stc.mklx
@@ -177,7 +177,7 @@
   [%c!alternative=\v!text,    % text | mathematics
    \c!left=,
    \c!right=,
-   \c!mathclass=\s!rel,
+   \c!mathclass=\s!relation,
    \c!alternative=\v!normal,
    \c!voffset=.25\mathexheight, % maybe less
    \c!hoffset=\zeropoint,
@@ -968,7 +968,7 @@
 \definemathstackers
   [\v!vfenced]
   [\v!both]
-  [\c!mathclass=\s!ord,
+  [\c!mathclass=\s!ordinary,
    \c!mathlimits=\v!yes]
 
 % these are needed for mathml:
@@ -1371,7 +1371,7 @@
    \fi
    \endgroup}
 
-\definemathstackers  [\v!wide] [\c!moffset=\thickmuskip,\c!mathclass=\s!rel]
+\definemathstackers  [\v!wide] [\c!moffset=\thickmuskip,\c!mathclass=\s!relation]
 
 \definemathunstacked [\v!wide] [And]       ["0026] % \mathrel{\;&\;}
 \definemathunstacked [\v!wide] [impliedby] ["27F8] % \mathrel{\;\Longleftarrow\;}
diff --git a/tex/context/base/mkxl/math-toy.mkxl b/tex/context/base/mkxl/math-toy.mkxl
index 510872e3b..34ea6f38c 100644
--- a/tex/context/base/mkxl/math-toy.mkxl
+++ b/tex/context/base/mkxl/math-toy.mkxl
@@ -20,16 +20,16 @@
 %D \starttyping
 %D \enabletrackers[math.toysymbol]
 %D
-%D \definemathtoysymbol[Plus] [bin][+]
-%D \definemathtoysymbol[Minus][bin][-]
-%D \definemathtoysymbol[Equal][rel][=]
+%D \definemathtoysymbol[Plus] [binary]  [+]
+%D \definemathtoysymbol[Minus][binary]  [-]
+%D \definemathtoysymbol[Equal][relation][=]
 %D
 %D $\dorecurse{199}{x_{#1} \ifodd#1\relax\Plus\else\Minus\fi} x_{200} \Equal n$ \blank
 %D \stoptyping
 
 \permanent\tolerant\protected\def\definemathtoysymbol[#1]#*[#2]#*[#3]%
   {\ifarguments\or\or\or
-     \setuevalue{#1}{\math_toy_define_symbol_indeed{\mathcodechecked{#2}}{#3}}%
+     \protected\instance\edefcsname#1\endcsname{\math_toy_define_symbol_indeed{\mathcodechecked{#2}}{#3}}%
    \fi}
 
 \protected\def\math_toy_define_symbol_traced#1#2%
diff --git a/tex/context/base/mkxl/mlib-lua.lmt b/tex/context/base/mkxl/mlib-lua.lmt
index 005a57a72..19423e7b1 100644
--- a/tex/context/base/mkxl/mlib-lua.lmt
+++ b/tex/context/base/mkxl/mlib-lua.lmt
@@ -127,7 +127,37 @@ local function same(p,n)
     return false
 end
 
-function inject.path(p,close,connector)
+-- function inject.path(p,close,connector)
+--     local closed = false
+--     local curled = false
+--     local n = #p
+-- print("spec",p,close,connector)
+--     if close == nil then
+--         closed = (p.close or p.cycle or p.closed) and true or false
+--     else
+--         closed = close
+--     end
+--     if connector then
+--         if connector == "auto" then
+--             connector = #p[1] > 2
+--         end
+--         if connector == false or connector == "--" then
+--             curled = true
+--      -- elseif connector == true or connector == ".." then
+--      --     if close and not same(p,n) then
+--      --         p[n+1] = p[1]
+--      --     end
+--         end
+--     elseif p.curled then
+--         curled = true
+--     end
+--     if trace then reporti("path") end
+--     inspect(p)
+--     print(p,closed,curled)
+--     return injectpath(currentmpx,p,closed,curled)
+-- end
+
+function inject.path(p,connector,close)
     local closed = false
     local curled = false
     local n = #p
@@ -142,10 +172,6 @@ function inject.path(p,close,connector)
         end
         if connector == false or connector == "--" then
             curled = true
-     -- elseif connector == true or connector == ".." then
-     --     if close and not same(p,n) then
-     --         p[n+1] = p[1]
-     --     end
         end
     elseif p.curled then
         curled = true
diff --git a/tex/context/base/mkxl/mlib-scn.lmt b/tex/context/base/mkxl/mlib-scn.lmt
index eb34d2b2e..dca2a7aa9 100644
--- a/tex/context/base/mkxl/mlib-scn.lmt
+++ b/tex/context/base/mkxl/mlib-scn.lmt
@@ -641,7 +641,8 @@ local function getparameterpath()
     if type(close) == "boolean" then
         n = n - 1
     else
-        close = false
+     -- close = false
+        close = nil
     end
     local connector = list[n]
     if type(connector) == "string" and validconnectors[connector] then
diff --git a/tex/context/base/mkxl/mult-sys.mkxl b/tex/context/base/mkxl/mult-sys.mkxl
index 9ac124808..caae5b365 100644
--- a/tex/context/base/mkxl/mult-sys.mkxl
+++ b/tex/context/base/mkxl/mult-sys.mkxl
@@ -160,6 +160,7 @@
 \definesystemconstant {leftclass}
 \definesystemconstant {rightclass}
 \definesystemconstant {clone}
+\definesystemconstant {close}
 \definesystemconstant {cmyk}
 \definesystemconstant {cm}
 \definesystemconstant {code}
@@ -308,8 +309,10 @@
 \definesystemconstant {nowidth}
 \definesystemconstant {numbering}
 \definesystemconstant {number}
+\definesystemconstant {open}
+\definesystemconstant {operator}
 \definesystemconstant {options}
-\definesystemconstant {ord}
+\definesystemconstant {ordinary}
 \definesystemconstant {orientation}
 \definesystemconstant {otr}
 \definesystemconstant {pagefloat}
@@ -326,7 +329,7 @@
 \definesystemconstant {register}
 \definesystemconstant {Regular}
 \definesystemconstant {regular}
-\definesystemconstant {rel}
+\definesystemconstant {relation}
 \definesystemconstant {reset}
 \definesystemconstant {reverse}
 \definesystemconstant {rgb}
diff --git a/tex/context/base/mkxl/pack-box.mkxl b/tex/context/base/mkxl/pack-box.mkxl
index bc73a80d7..8c83f8308 100644
--- a/tex/context/base/mkxl/pack-box.mkxl
+++ b/tex/context/base/mkxl/pack-box.mkxl
@@ -1304,6 +1304,9 @@
 
 \permanent\protected\def\mathboxanchored#1#2{#2\Umathsource\namedboxanchor{#1}\relax}
 
+\permanent\protected\def\mathrowanchored #1{\alignmentwrapsource\namedboxanchor{#1}\relax}
+\permanent\protected\def\mathcellanchored#1{\alignmentcellsource\namedboxanchor{#1}\relax}
+
 % to be used as:
 %
 % \scratchcounter\registeredboxanchor
diff --git a/tex/context/base/mkxl/strc-itm.mklx b/tex/context/base/mkxl/strc-itm.mklx
index 13b750ce3..96e98e769 100644
--- a/tex/context/base/mkxl/strc-itm.mklx
+++ b/tex/context/base/mkxl/strc-itm.mklx
@@ -1044,7 +1044,7 @@
    \ifconditional\c_strc_itemgroups_text
      \removeunwantedspaces
      \space
-     \ignorespaces
+     \ignorepars % \ignorespaces
    \else
      \par
    \fi
@@ -1238,18 +1238,19 @@
   {\settrue\c_strc_itemgroups_head
    \dotagsetitem\s!head% % weird place
    \dostarttagged\t!itemhead\empty
-   \useitemgroupstyleandcolor\c!headstyle\c!headcolor\ignorespaces}
+   \useitemgroupstyleandcolor\c!headstyle\c!headcolor
+   \ignorepars} % \ignorespaces
 
 \protected\def\strc_itemgroups_stop_head_indeed
   {\removeunwantedspaces
    \dostoptagged
    \ifconditional\c_strc_itemgroups_inline_head
        \space
-       \ignorespaces
+       \ignorepars % \ignorespaces
    \else
      \ifconditional\c_strc_itemgroups_text
        \space
-       \ignorespaces
+       \ignorepars % \ignorespaces
      \else
        \par
      \fi
@@ -1261,7 +1262,7 @@
 \protected\def\strc_itemgroups_head_body_indeed
   {\dostarttagged\t!itembody\empty
    \noindentation
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 % Simple commands.
 
@@ -1274,7 +1275,7 @@
   %\advance\c_strc_itemgroups_n_of_items\plusone
    \setbox\b_strc_itemgroups\emptyhbox
    \strc_itemgroups_check_for_repeated
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \protected\def\strc_itemgroups_start_button[#destination]%
   {\edef\m_strc_itemgroups_destination{#destination}%
@@ -1349,6 +1350,7 @@
 \letcsname\??itemgroupstart\v!its \endcsname\strc_itemgroups_start_items
 \letcsname\??itemgroupstart\v!mar \endcsname\strc_itemgroups_start_margin
 \letcsname\??itemgroupstart\v!txt \endcsname\strc_itemgroups_start_text
+\letcsname\??itemgroupstart\v!no  \endcsname\strc_itemgroups_start_no_item
 
 \def\strc_itemgroups_optimize_breaks
   {\ifcase\c_strc_itemgroups_column_depth
@@ -1552,7 +1554,7 @@
    \ifconditional\c_strc_itemgroups_indented_first
      \hskip\parindent
    \fi
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \def\strc_itemgroups_start_item_nop
   {\let\currentitemreference\empty
@@ -1562,7 +1564,7 @@
      {\useitemgroupstyleandcolor\c!style\c!color
       \strc_itemgroups_used_symbol}%
    \strc_itemgroups_check_for_repeated
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \setvalue{\??itemgroupdistance\v!none}%
   {\let\m_strc_itemgroups_text_distance\zeropoint}
@@ -1596,7 +1598,7 @@
 %    \ignorespaces}
 
 \protected\def\strc_itemgroups_default_command
-  {\ignorespaces}
+  {\ignorepars} % \ignorespaces
 
 %D Special case:
 
@@ -1818,7 +1820,7 @@
 %    \setbox\scratchbox\hbox{\settrialtypesetting#text}%
 %    \setbox\scratchbox\hbox\ifdim\wd\scratchbox<1em to 1.5\else spread 1\fi em{#text\hfil}%
 %    \normalexpanded{\box\scratchbox\endgroup\hangindent\the\wd\scratchbox}%
-%    \ignorespaces}
+%    \ignorepars} % \ignorespaces
 
 %D End of plugin.
 
@@ -1846,7 +1848,7 @@
    \ht\b_strc_itemgroups\strutheight
    \dp\b_strc_itemgroups\strutdepth
    \box\b_strc_itemgroups
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 %D Done again.
 
diff --git a/tex/context/base/mkxl/supp-box.mkxl b/tex/context/base/mkxl/supp-box.mkxl
index fe96505a0..deb2699d7 100644
--- a/tex/context/base/mkxl/supp-box.mkxl
+++ b/tex/context/base/mkxl/supp-box.mkxl
@@ -675,20 +675,32 @@
 \def\syst_boxes_do_tlap{\vpack to \zeropoint{\vss\box\nextbox}\endgroup}
 \def\syst_boxes_do_blap{\vpack to \zeropoint{\box\nextbox\vss}\endgroup}
 
-\def\syst_boxes_rlap     {\begingroup\dowithnextboxcs\syst_boxes_do_rlap\hbox}
-\def\syst_boxes_llap     {\begingroup\dowithnextboxcs\syst_boxes_do_llap\hbox}
-\def\syst_boxes_clap     {\begingroup\dowithnextboxcs\syst_boxes_do_clap\hbox}
-\def\syst_boxes_math_clap{\mathpalette\syst_boxes_do_math_clap}
-\def\syst_boxes_math_llap{\mathpalette\syst_boxes_do_math_llap}
-\def\syst_boxes_math_rlap{\mathpalette\syst_boxes_do_math_rlap}
+\protected\def\syst_boxes_rlap{\begingroup\dowithnextboxcs\syst_boxes_do_rlap\hbox}
+\protected\def\syst_boxes_llap{\begingroup\dowithnextboxcs\syst_boxes_do_llap\hbox}
+\protected\def\syst_boxes_clap{\begingroup\dowithnextboxcs\syst_boxes_do_clap\hbox}
 
-\def\syst_boxes_do_math_clap#1#2{\syst_boxes_clap{\normalstartimath\mathsurround\zeropoint#1#2\normalstopimath}}
-\def\syst_boxes_do_math_llap#1#2{\syst_boxes_llap{\normalstartimath\mathsurround\zeropoint#1#2\normalstopimath}}
-\def\syst_boxes_do_math_rlap#1#2{\syst_boxes_rlap{\normalstartimath\mathsurround\zeropoint#1#2\normalstopimath}}
+% \def\syst_boxes_do_math_clap#1#2{\syst_boxes_clap{\normalstartimath\mathsurround\zeropoint#1#2\normalstopimath}}
+% \def\syst_boxes_do_math_llap#1#2{\syst_boxes_llap{\normalstartimath\mathsurround\zeropoint#1#2\normalstopimath}}
+% \def\syst_boxes_do_math_rlap#1#2{\syst_boxes_rlap{\normalstartimath\mathsurround\zeropoint#1#2\normalstopimath}}
+%
+% \def\syst_boxes_math_clap{\mathpalette\syst_boxes_do_math_clap}
+% \def\syst_boxes_math_llap{\mathpalette\syst_boxes_do_math_llap}
+% \def\syst_boxes_math_rlap{\mathpalette\syst_boxes_do_math_rlap}
+
+\def\syst_boxes_math_xlap#1#2%
+  {\normalexpanded{#1\bgroup\normalstartimath\Ustyle\the\mathstyle}%
+ %{\expandafter#1\expandafter\bgroup\expandafter\normalstartimath\expandafter\Ustyle\the\mathstyle
+     \mathsurround\zeropoint#2%
+   \normalstopimath\egroup}
+
+\def\syst_boxes_math_clap{\syst_boxes_math_xlap\syst_boxes_clap}
+\def\syst_boxes_math_llap{\syst_boxes_math_xlap\syst_boxes_llap}
+\def\syst_boxes_math_rlap{\syst_boxes_math_xlap\syst_boxes_rlap}
 
 \permanent\protected\def\rlap{\mathortext\syst_boxes_math_rlap\syst_boxes_rlap}
 \permanent\protected\def\llap{\mathortext\syst_boxes_math_llap\syst_boxes_llap}
 \permanent\protected\def\clap{\mathortext\syst_boxes_math_clap\syst_boxes_clap}
+
 \permanent\protected\def\tlap{\begingroup\dowithnextboxcs\syst_boxes_do_tlap\vbox}
 \permanent\protected\def\blap{\begingroup\dowithnextboxcs\syst_boxes_do_blap\vbox}
 
diff --git a/tex/context/base/mkxl/tabl-tab.mkxl b/tex/context/base/mkxl/tabl-tab.mkxl
index d9aa5e7fa..01e665d02 100644
--- a/tex/context/base/mkxl/tabl-tab.mkxl
+++ b/tex/context/base/mkxl/tabl-tab.mkxl
@@ -756,7 +756,7 @@
    \!taDimenB=#2\relax
    \let\!TsSpaceFactor\empty
    \ifmmode
-     \expandafter\mathpalette
+     \expandafter\mathpalette % (*) the only place where still use this
      \expandafter\!TsEnlargeMath
    \else
      \expandafter\!TsEnlargeOther
@@ -1040,7 +1040,7 @@
 \def\tabl_table_Smash
   {\relax
    \ifmmode
-     \expandafter\mathpalette
+     \expandafter\mathpalette % (*)
      \expandafter\!thDoMathVCS
    \else
      \expandafter\!thDoVCS
@@ -1079,7 +1079,7 @@
    \fi
    \!taDimenA\!thSign\!taDimenA\relax
    \ifmmode
-     \expandafter\mathpalette
+     \expandafter\mathpalette % (*)
      \expandafter\!thDoMathRaise
    \else
      \expandafter\!thDoSimpleRaise
diff --git a/tex/context/base/mkxl/tabl-tbl.mkxl b/tex/context/base/mkxl/tabl-tbl.mkxl
index 959ef4617..cd3d3d02d 100644
--- a/tex/context/base/mkxl/tabl-tbl.mkxl
+++ b/tex/context/base/mkxl/tabl-tbl.mkxl
@@ -1598,7 +1598,7 @@
    \ifnum\c_tabl_tabulate_column>\c_tabl_tabulate_columns\relax
      \expandafter\NR
    \else
-     \expandafter\ignorespaces % interferes with the more tricky hooks
+     \expandafter\ignorepars % \ignorespaces % interferes with the more tricky hooks
    \fi}
 
 \protected\def\tabl_tabulate_set_quick#1% see \startlegend \startgiven (for the moment still public)
@@ -1955,7 +1955,20 @@
     \enforced\let\AR\NR
 \to \t_tabl_tabulate_initializers_first
 
-\permanent\protected\def\tabl_tabulate_NR_common#1#2%
+% \permanent\protected\def\tabl_tabulate_NR_common#1#2%
+%   {\global\advance\c_tabl_tabulate_noflines\plusone
+%    \global\setfalse\c_tabl_tabulate_firstflushed
+%    \global\setfalse\c_tabl_tabulate_equal
+%    \global\c_tabl_tabulate_column\zerocount
+%    \ifconditional#1\relax
+%      \tabl_tabulate_break_state_reset
+%    \fi
+%    \tabl_tabulate_pheight_reset
+%    \unskip\unskip\crcr\tabl_tabulate_flush_collected
+%    % can we omit the next one in the first run? probably
+%    \noalign{\the\t_tabl_tabulate_every_after_row#2}}
+
+\permanent\protected\def\tabl_tabulate_NR_common#1#2#.#3% #. gobbles pars and spaces
   {\global\advance\c_tabl_tabulate_noflines\plusone
    \global\setfalse\c_tabl_tabulate_firstflushed
    \global\setfalse\c_tabl_tabulate_equal
@@ -1966,7 +1979,7 @@
    \tabl_tabulate_pheight_reset
    \unskip\unskip\crcr\tabl_tabulate_flush_collected
    % can we omit the next one in the first run? probably
-   \noalign{\the\t_tabl_tabulate_every_after_row#2}}
+   \noalign{\the\t_tabl_tabulate_every_after_row#2}#3}
 
 \def\tabl_tabulate_check_penalties
   {\ifconditional\c_tabl_tabulate_tolerant_break\else
@@ -2020,8 +2033,8 @@
      \ifconditional\c_tabl_tabulate_automode\hsize\d_tabl_tabulate_width\fi
      % \begstrut % interferes with pre-\pars
      % evt: \appendtoks\begstrut\to\everypar
-     \ignorespaces
      \let\tabl_tabulate_eskip\tabl_tabulate_eskip_second
+     \expandafter\ignorepars % \ignorespaces
    \else
      % successive lines
      \let\tabl_tabulate_eskip\empty
@@ -2054,7 +2067,7 @@
      \ifconditional\c_tabl_tabulate_automode\hsize\d_tabl_tabulate_width\fi
      % \begstrut % interferes with pre-\pars
      % evt: \appendtoks\begstrut\to\everypar
-     \ignorespaces}
+     \ignorepars} % \ignorespaces
 
 \protected\def\tabl_tabulate_eskip_second_split_nop % vertical strut added august 2003
   {\par\verticalstrut
@@ -2902,7 +2915,7 @@
    \ifcase\c_tabl_tabulate_column\or
      \tabl_register_row_background{#1}%
    \fi
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \pushoverloadmode
 
@@ -2913,7 +2926,7 @@
        \ifcase\c_tabl_tabulate_column\or
          \tabl_register_row_background\m_table_current_row_background_default
        \fi
-       \ignorespaces}
+       \ignorepars} % \ignorespaces
 
 \popoverloadmode
 
@@ -2923,7 +2936,7 @@
      \tabl_register_row_background{#1}%
    \fi
    \usetabulationstyleandcolor\c!foregroundstyle\c!foregroundcolor
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \permanent\protected\def\tabl_tabulate_DB_first
   {\tabl_tabulate_column_normal\plusone\zerocount\relax
@@ -2932,21 +2945,21 @@
    \fi
    \enforced\let\fontstyle\globalfontstyle
    \usetabulationstyleandcolor\c!foregroundstyle\c!foregroundcolor
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \permanent\protected\def\tabl_tabulate_NF_first[#1]%
   {\tabl_tabulate_column_normal\zerocount\zerocount\relax
    \ifcase\c_tabl_tabulate_column\or
      \tabl_register_row_background_filler{#1}%
    \fi
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \permanent\protected\def\tabl_tabulate_NP_first
   {\tabl_tabulate_column_normal\zerocount\zerocount\relax
    \ifcase\c_tabl_tabulate_column\or
      \tabl_register_row_background_filler\m_table_current_row_background_default_filler
    \fi
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \permanent\protected\def\tabl_tabulate_FB_first[#1]%
   {\tabl_tabulate_column_normal\plusone\zerocount\relax
@@ -2954,7 +2967,7 @@
      \tabl_register_row_background_filler{#1}%
    \fi
    \usetabulationstyleandcolor\c!foregroundstyle\c!foregroundcolor
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \permanent\protected\def\tabl_tabulate_PB_first
   {\tabl_tabulate_column_normal\plusone\zerocount\relax
@@ -2963,7 +2976,7 @@
    \fi
    \enforced\let\fontstyle\globalfontstyle
    \usetabulationstyleandcolor\c!foregroundstyle\c!foregroundcolor
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \pushoverloadmode
 
@@ -2999,7 +3012,7 @@
    \iftrialtypesetting\orelse\ifcase\c_tabl_tabulate_column\or
      \tabl_tabulate_A_first
    \fi
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \permanent\protected\def\tabl_tabulate_BA_first
   {\tabl_tabulate_column_normal\plusone\zerocount\relax
@@ -3007,7 +3020,7 @@
      \tabl_tabulate_A_first
    \fi
    \usetabulationstyleandcolor\c!foregroundstyle\c!foregroundcolor
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \appendtoks
     \enforced\let\NL\tabl_tabulate_NL_first % NC with Line
@@ -3065,7 +3078,7 @@
   {\NC\loopcs{#1}\tabl_tabulate_span
    \gdef\tabl_tabulate_kooh{\begincsname\??tabulatespana#2\endcsname}%
    \begincsname\??tabulatespanb#2\endcsname
-   \ignorespaces}
+   \ignorepars} % \ignorespaces
 
 \appendtoks
     \enforced\let\NS\tabl_tabulate_NS
diff --git a/tex/context/base/mkxl/toks-aux.lmt b/tex/context/base/mkxl/toks-aux.lmt
index f1bac2093..e1d3fabf4 100644
--- a/tex/context/base/mkxl/toks-aux.lmt
+++ b/tex/context/base/mkxl/toks-aux.lmt
@@ -176,21 +176,22 @@ local function getthem(getter,post)
     return utilities.storage.allocate(table.swapped(codes,codes))
 end
 
-tex.discoptioncodes    = getthem(tex.getdiscoptionvalues,    "discoptioncode")
-tex.flagcodes          = getthem(tex.getflagvalues,          "flagcode" )
-tex.frozenparcodes     = getthem(tex.getfrozenparvalues,     "frozenparcode")
-tex.glyphoptioncodes   = getthem(tex.getglyphoptionvalues,   "glyphoptioncode")
-tex.groupcodes         = getthem(tex.getgroupvalues,         "groupcode")
-tex.hyphenationcodes   = getthem(tex.gethyphenationvalues,   "hyphenationcode")
-tex.mathcontrolcodes   = getthem(tex.getmathcontrolvalues,   "mathcontrolcode")
----.mathflattencodes   = getthem(tex.getmathflattenvalues,   "mathflattencode")
-tex.noadoptioncodes    = getthem(tex.getnoadoptionvalues,    "") -- only at lua end
-tex.normalizecodes     = getthem(tex.getnormalizevalues,     "normalizecode")
-tex.automigrationcodes = getthem(tex.getautomigrationvalues, "automigrationcode") -- only at lua end
-tex.parcontextcodes    = getthem(tex.getparcontextvalues,    "parcontextcode")
-tex.textcontrolcodes   = getthem(tex.gettextcontrolvalues,   "") -- only at lua end
-tex.listanchorcodes    = getthem(tex.getlistanchorvalues,    "listanchorcode")
-tex.listsigncodes      = getthem(tex.getlistsignvalues,      "listsigncode")
+tex.discoptioncodes    = getthem(tex.getdiscoptionvalues,      "discoptioncode")
+tex.flagcodes          = getthem(tex.getflagvalues,            "flagcode" )
+tex.frozenparcodes     = getthem(tex.getfrozenparvalues,       "frozenparcode")
+tex.glyphoptioncodes   = getthem(tex.getglyphoptionvalues,     "glyphoptioncode")
+tex.groupcodes         = getthem(tex.getgroupvalues,           "groupcode")
+tex.hyphenationcodes   = getthem(tex.gethyphenationvalues,     "hyphenationcode")
+tex.mathcontrolcodes   = getthem(tex.getmathcontrolvalues,     "mathcontrolcode")
+---.mathflattencodes   = getthem(tex.getmathflattenvalues,     "mathflattencode")
+tex.noadoptioncodes    = getthem(tex.getnoadoptionvalues,      "") -- only at lua end
+tex.normalizecodes     = getthem(tex.getnormalizevalues,       "normalizecode")
+tex.automigrationcodes = getthem(tex.getautomigrationvalues,   "automigrationcode") -- only at lua end
+tex.parcontextcodes    = getthem(tex.getparcontextvalues,      "parcontextcode")
+tex.textcontrolcodes   = getthem(tex.gettextcontrolvalues,     "") -- only at lua end
+tex.listanchorcodes    = getthem(tex.getlistanchorvalues,      "listanchorcode")
+tex.listsigncodes      = getthem(tex.getlistsignvalues,        "listsigncode")
+tex.classoptioncodes   = getthem(tex.getmathclassoptionvalues, "classoptioncode")
 
 function tex.stringtocodesbitmap(str,codes)
     local bitmap = 0
diff --git a/tex/context/base/mkxl/trac-vis.lmt b/tex/context/base/mkxl/trac-vis.lmt
index 57583bf3c..be30ce34b 100644
--- a/tex/context/base/mkxl/trac-vis.lmt
+++ b/tex/context/base/mkxl/trac-vis.lmt
@@ -1230,7 +1230,7 @@ local ruledstrut do
             setattr(current,a_layer,l_strut)
             head, current = insertnodeafter(head,current,new_kern(-strut_size))
         end
-        return head, getnext(current)
+        return head, current
     end
 
 end
diff --git a/tex/context/fonts/mkiv/asana-math.lfg b/tex/context/fonts/mkiv/asana-math.lfg
index 0e8beb9e3..6177cb831 100644
--- a/tex/context/fonts/mkiv/asana-math.lfg
+++ b/tex/context/fonts/mkiv/asana-math.lfg
@@ -77,6 +77,17 @@ return {
                     }
                 },
                 -- {
+                --     tweak = "kerns",
+                --     list  = {
+                --         [0x2F] = {
+                            -- topleft     = -0.2,
+                            -- bottomleft  =  0,
+                            -- topright    =  0,
+                            -- bottomright =  -0.2,
+                --        },
+                --     },
+                -- },
+                -- {
                 --     tweak   = "fixprimes",
                 --     factor  = 0.85,
                 --     scale   = 0.65,
diff --git a/tex/context/fonts/mkiv/bonum-math.lfg b/tex/context/fonts/mkiv/bonum-math.lfg
index af1df417d..1e96c7a6b 100644
--- a/tex/context/fonts/mkiv/bonum-math.lfg
+++ b/tex/context/fonts/mkiv/bonum-math.lfg
@@ -152,6 +152,17 @@ return {
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.15,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright = -0.15,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                    --  scale   = 0.8,
                    --  smaller = true,
diff --git a/tex/context/fonts/mkiv/cambria-math.lfg b/tex/context/fonts/mkiv/cambria-math.lfg
index 4fe564cea..f73bc3ab7 100644
--- a/tex/context/fonts/mkiv/cambria-math.lfg
+++ b/tex/context/fonts/mkiv/cambria-math.lfg
@@ -94,6 +94,17 @@ return {
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     scale   = 0.9,
                     -- smaller = true,
@@ -122,6 +133,9 @@ return {
                 {
                     tweak = "addrules",
                 },
+                {
+                    tweak = "wipecues",
+                },
             },
         },
         bigslots = {
diff --git a/tex/context/fonts/mkiv/concrete-math.lfg b/tex/context/fonts/mkiv/concrete-math.lfg
index ecd910eb0..59ea0f2ea 100644
--- a/tex/context/fonts/mkiv/concrete-math.lfg
+++ b/tex/context/fonts/mkiv/concrete-math.lfg
@@ -17,6 +17,17 @@ return {
              --     tweak   = "fixprimes",
              --     factor  = 0.9,
              -- },
+                {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                        },
+                    },
+                },
             },
         },
         bigslots = {
diff --git a/tex/context/fonts/mkiv/dejavu-math.lfg b/tex/context/fonts/mkiv/dejavu-math.lfg
index 3c262fab5..01eaefd80 100644
--- a/tex/context/fonts/mkiv/dejavu-math.lfg
+++ b/tex/context/fonts/mkiv/dejavu-math.lfg
@@ -38,6 +38,17 @@ return {
                     }
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     -- scale   = 0.9,
                     -- smaller = true,
@@ -55,6 +66,9 @@ return {
                 {
                     tweak = "addrules",
                 },
+                {
+                    tweak = "wipecues",
+                },
             },
         },
         alternates = {
diff --git a/tex/context/fonts/mkiv/erewhon-math.lfg b/tex/context/fonts/mkiv/erewhon-math.lfg
index d5b576f76..0924f7f13 100644
--- a/tex/context/fonts/mkiv/erewhon-math.lfg
+++ b/tex/context/fonts/mkiv/erewhon-math.lfg
@@ -16,6 +16,17 @@ return {
         tweaks = {
             aftercopying = {
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.15,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.15,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     factor  = 0.9,
                     scale   = 0.9,
diff --git a/tex/context/fonts/mkiv/garamond-math.lfg b/tex/context/fonts/mkiv/garamond-math.lfg
index b002cc942..4c5eb5ba6 100644
--- a/tex/context/fonts/mkiv/garamond-math.lfg
+++ b/tex/context/fonts/mkiv/garamond-math.lfg
@@ -94,6 +94,17 @@ return {
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     scale   = 0.9,
                     -- smaller = true,
diff --git a/tex/context/fonts/mkiv/kpfonts-math.lfg b/tex/context/fonts/mkiv/kpfonts-math.lfg
index 695a6af32..490b7b297 100644
--- a/tex/context/fonts/mkiv/kpfonts-math.lfg
+++ b/tex/context/fonts/mkiv/kpfonts-math.lfg
@@ -23,6 +23,17 @@ return {
                         -- whatever
                     },
                 },
+                {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
              -- {
              --     tweak   = "fixprimes",
              --     factor  = 0.85, -- accent base height
diff --git a/tex/context/fonts/mkiv/libertinus-math.lfg b/tex/context/fonts/mkiv/libertinus-math.lfg
index 3930ce8e2..2d683cc3c 100644
--- a/tex/context/fonts/mkiv/libertinus-math.lfg
+++ b/tex/context/fonts/mkiv/libertinus-math.lfg
@@ -61,6 +61,17 @@ return {
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.15,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.15,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     scale   = 0.9,
                  -- smaller = true,
diff --git a/tex/context/fonts/mkiv/lm.lfg b/tex/context/fonts/mkiv/lm.lfg
index 58db0e3a4..44ea14571 100644
--- a/tex/context/fonts/mkiv/lm.lfg
+++ b/tex/context/fonts/mkiv/lm.lfg
@@ -90,6 +90,17 @@ return {
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     factor  = 1.05,
                     -- smaller = true,
diff --git a/tex/context/fonts/mkiv/lucida-opentype-math.lfg b/tex/context/fonts/mkiv/lucida-opentype-math.lfg
index 6dc6eef2a..72f4ca9e6 100644
--- a/tex/context/fonts/mkiv/lucida-opentype-math.lfg
+++ b/tex/context/fonts/mkiv/lucida-opentype-math.lfg
@@ -37,7 +37,7 @@ return {
             NoLimitSupFactor               =   0,
             NoLimitSubFactor               = 900,
             FractionRuleThickness          =  55,
-         -- AccentBaseHeight               = 650,
+            -- AccentBaseHeight               = 650,
             AccentBaseDepth                = 150,
         },
         tweaks = {
@@ -46,13 +46,13 @@ return {
                     tweak    = "version",
                     expected = "Version 1.802",
                 },
-                {
-                    tweak = "substitutes",
-                    list  = {
-                        [0x2264] = "ss03",
-                        [0x2265] = "ss03",
-                    }
-                },
+                -- {
+                --     tweak = "substitutes",
+                --     list  = {
+                --         [0x2264] = "ss03",
+                --         [0x2265] = "ss03",
+                --     }
+                -- },
                 -- \definefontfeature[mathlucida][copymathscripts=yes]
                 -- \definefontfeature[mathlucida][copymathscripts=yes,ss04=yes]
                 -- 0xFEOO should be chancery style, if present
@@ -79,12 +79,28 @@ return {
                         ["0x23DD.parts.1"]  = { xoffset = -0.075, depth  = .8, yoffset =  0.2 },
                         ["0x23DD.parts.2"]  = {                   depth  = .8, yoffset =  0.2 },
                         ["0x23DD.parts.3"]  = { xoffset =  0.075, depth  = .8, yoffset =  0.2 },
+                        -- The < and > are slightly too small. We scale them by 867/795
+                        ["0x003C"]          = { scale = 1.09057, width = 1.09057, height = 1.09057},
+                        ["0x003E"]          = { scale = 1.09057, width = 1.09057, height = 1.09057},
+                        -- The = is too big if in ss03. We scale it by 795/867 (not working like this)
+                        -- ["0x003D.ss03"]     = { scale = 0.916955, width = 0.916955, height = 0.916955},
                         -- these are done later using the AccentBase* parameters
                      -- [0x23DC]  = { height = .2, yoffset = -0.8 },
                      -- [0x23DD]  = { depth  = .6, yoffset =  0.4 },
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                   tweak   = "fixprimes",
                   factor  = 0.8, -- accent base height
                --    smaller = true, -- replace multiples
diff --git a/tex/context/fonts/mkiv/pagella-math.lfg b/tex/context/fonts/mkiv/pagella-math.lfg
index db2f30a0a..d1e77e9bf 100644
--- a/tex/context/fonts/mkiv/pagella-math.lfg
+++ b/tex/context/fonts/mkiv/pagella-math.lfg
@@ -111,7 +111,19 @@ return {
                         [0x1D712] = { 0.1,   1.2,  0.1       }, -- \chi
                         [0x1D713] = { -0.05, 0.95, 0.1       }, -- \psi
                         [0x1D71D] = { 0,     1,    0,   0.7  }, -- \varpi
-                        },
+                    },
+                },
+                {
+                    tweak = "kerns",
+                    list  = {
+                    -- ["*:0x2F"] = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright = -0.2,
+                       },
+                    },
                 },
                 {
                     tweak   = "fixprimes",
diff --git a/tex/context/fonts/mkiv/schola-math.lfg b/tex/context/fonts/mkiv/schola-math.lfg
index 33efb6892..cea6b501c 100644
--- a/tex/context/fonts/mkiv/schola-math.lfg
+++ b/tex/context/fonts/mkiv/schola-math.lfg
@@ -36,6 +36,17 @@ return {
                     }
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     scale   = 0.85,
                     -- smaller = true,
diff --git a/tex/context/fonts/mkiv/stix-two-math.lfg b/tex/context/fonts/mkiv/stix-two-math.lfg
index 6943e86ad..351c6a8ee 100644
--- a/tex/context/fonts/mkiv/stix-two-math.lfg
+++ b/tex/context/fonts/mkiv/stix-two-math.lfg
@@ -32,6 +32,17 @@ return {
                     tweak    = "version",
                     expected = "Version 2.12 b168",
                 },
+                {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
                 -- 0xFEOO should be chancery style, if present
                 {
                     tweak    = "variants",
diff --git a/tex/context/fonts/mkiv/termes-math.lfg b/tex/context/fonts/mkiv/termes-math.lfg
index 2ad93c30b..45eaa0505 100644
--- a/tex/context/fonts/mkiv/termes-math.lfg
+++ b/tex/context/fonts/mkiv/termes-math.lfg
@@ -57,6 +57,17 @@ return {
                     },
                 },
                 {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.2,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.2,
+                       },
+                    },
+                },
+                {
                     tweak   = "fixprimes",
                     scale   = 0.85,
                   --  smaller = true,
diff --git a/tex/context/fonts/mkiv/type-imp-newcomputermodern.mkiv b/tex/context/fonts/mkiv/type-imp-newcomputermodern.mkiv
index 00b9cb964..1c9788a98 100644
--- a/tex/context/fonts/mkiv/type-imp-newcomputermodern.mkiv
+++ b/tex/context/fonts/mkiv/type-imp-newcomputermodern.mkiv
@@ -49,8 +49,8 @@
 
     \starttypescript [\s!math][newcomputermodern] [\s!name]
       % \loadfontgoodies[newcomputermodern-math] ,\s!goodies=newcomputermodern-math
-        \definefontsynonym[\s!MathRoman]    [\s!file:newcmmath-regular][\s!features={\s!math\mathsizesuffix,mathextra},\s!goodies=newcomputermodern-math]
-        \definefontsynonym[\s!MathRomanBold][\s!file:newcmmath-regular][\s!features={\s!math\mathsizesuffix,newcomputermodern-math-bold,mathextra}\s!goodies=newcomputermodern-math]
+        \definefontsynonym[\s!MathRoman]    [\s!file:newcmmath-regular][\s!features={\s!math\mathsizesuffix,mathextra},\s!goodies=lm]
+        \definefontsynonym[\s!MathRomanBold][\s!file:newcmmath-regular][\s!features={\s!math\mathsizesuffix,newcomputermodern-math-bold,mathextra}\s!goodies=lm]
     \stoptypescript
 
     \starttypescript [\s!serif] [newcomputermodern-book] [\s!name]
diff --git a/tex/context/fonts/mkiv/xits-math.lfg b/tex/context/fonts/mkiv/xits-math.lfg
index 6c4ac8b66..dfb0e54bb 100644
--- a/tex/context/fonts/mkiv/xits-math.lfg
+++ b/tex/context/fonts/mkiv/xits-math.lfg
@@ -21,6 +21,17 @@ return {
                     tweak    = "version",
                     expected = "Version 1.302",
                 },
+                {
+                    tweak = "kerns",
+                    list  = {
+                        [0x2F] = {
+                            topleft     = -0.1,
+                         -- bottomleft  =  0,
+                         -- topright    =  0,
+                            bottomright =  -0.1,
+                       },
+                    },
+                },
                 -- 0xFEOO should be chancery style, if present
                 {
                     tweak    = "variants",
diff --git a/tex/generic/context/luatex/luatex-fonts-merged.lua b/tex/generic/context/luatex/luatex-fonts-merged.lua
index ab4f8a66d..966b918c1 100644
--- a/tex/generic/context/luatex/luatex-fonts-merged.lua
+++ b/tex/generic/context/luatex/luatex-fonts-merged.lua
@@ -1,6 +1,6 @@
 -- merged file : c:/data/develop/context/sources/luatex-fonts-merged.lua
 -- parent file : c:/data/develop/context/sources/luatex-fonts.lua
--- merge date  : 2022-03-24 21:14
+-- merge date  : 2022-04-01 09:33
 
 do -- begin closure to overcome local limits and interference