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1\setupbodyfont[dejavu]
2
3\startluacode
4    fonts.handlers.otf.addfeature {
5        name = "kerntest",
6        type = "kern",
7        data = {
8            A = { B = -500 },
9        }
10    }
11\stopluacode
12
13\starttext
14
15\definecolor[tgray][s=.5,t=.5,a=1] \showfontkerns \showglyphs
16
17\definefontfeature[kerntest] [mode=node,kerntest=yes]
18
19\definedfont[file:dejavu-serif.ttf*kerntest @ 48pt]
20
21\startTEXpage[offset=10pt,foregroundcolor=tgray]
22    ABCDEF
23\stopTEXpage
24
25\stoptext
26