Hans, I’m afraid that underscore hyphenation has issues with font expansion: \startluacode function document.addfunnyhyphen(tfmdata) local underscore = utf.byte("_") local char = tfmdata.characters[underscore] if not char then return end tfmdata.characters[0xFE000] = { width = 0, height = 0, depth = 0, commands = { { "right", -char.width }, { "down", char.depth }, { "slot", 1, underscore }, } } end utilities.sequencers.appendaction("aftercopyingcharacters", "after","document.addfunnyhyphen") local shared = { start = 1, length = 1, before = utf.char(0xFE000), after = nil, left = false, right = false, } local all = table.setmetatableindex({ }, function(t,k) return shared end) languages.hyphenators.traditional.installmethod("sha", function(dictionary,word,n) return all end) \stopluacode \definehyphenationfeatures [sha] [characters=all, alternative=sha, righthyphenchar="FE000] \definefontfeature [default] [default] [expansion=quality] \setupalign[hz] \sethyphenationfeatures[sha]% \setuphyphenation[method=traditional]% \starttext \hsize\zeropoint abcde \stoptext Many thanks for your help, Pablo -- http://www.ousia.tk