/usr/share/texmf/tex/context/interface/ is in context-modules 20140528-2.
This file is owned by root:root, with mode 0o755.
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/usr/share/texmf/tex/context/interface/third/
/usr/share/texmf/tex/context/interface/third/lettrine.xml
/usr/share/texmf/tex/context/interface/third/t-account.xml
/usr/share/texmf/tex/context/interface/third/t-cyrillicnumbers.xml
/usr/share/texmf/tex/context/interface/third/t-fullpage.xml
/usr/share/texmf/tex/context/interface/third/t-letter.xml
/usr/share/texmf/tex/context/interface/third/t-mathsets.xml
/usr/share/texmf/tex/context/interface/third/t-memo.xml
/usr/share/texmf/tex/context/interface/third/t-rst.xml
/usr/share/texmf/tex/context/interface/third/t-simpleslides.xml
/usr/share/texmf/tex/context/interface/third/t-transliterator.xml