Hi Hans,

this is a bug report thanks to Khaled:

  http://tex.stackexchange.com/a/126650/14066

In short: the font loader applies the kerning of libertine
version 5.3.0 even though this appears to be broken in the font.
Context translation of the example:

  \definefontfeature [kerning] [mode=node,smcp=yes,kern=yes]
  \definefont [libertineserifsmallcaps] [file:LinLibertine_R.otf*kerning]
  \definefont [libertinesanssmallcaps]  [file:LinBiolinum_R.otf*kerning]

  \def\demotext{Vacillate Vaccine Vapour Vanish Va...}

  \starttext
    {\libertineserifsmallcaps \demotext}\par
    {\libertinesanssmallcaps  \demotext}\par
  \stoptext

(Doesn’t occur in base mode.) The technical details are in the
thread Khaled references.

Best regards,
Philipp


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