/usr/share/texmf/tex/context/ is in pgf 2.10-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/texmf/tex/context/third/
/usr/share/texmf/tex/context/third/pgf/
/usr/share/texmf/tex/context/third/pgf/basiclayer/
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgf.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbim.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbla.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbma.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbpl.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbpt.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbsh.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfbsn.tex
/usr/share/texmf/tex/context/third/pgf/basiclayer/t-pgfcor.tex
/usr/share/texmf/tex/context/third/pgf/frontendlayer/
/usr/share/texmf/tex/context/third/pgf/frontendlayer/t-tikz.tex
/usr/share/texmf/tex/context/third/pgf/math/
/usr/share/texmf/tex/context/third/pgf/math/t-pgfmat.tex
/usr/share/texmf/tex/context/third/pgf/systemlayer/
/usr/share/texmf/tex/context/third/pgf/systemlayer/t-pgfsys.tex
/usr/share/texmf/tex/context/third/pgf/utilities/
/usr/share/texmf/tex/context/third/pgf/utilities/t-pgfcal.tex
/usr/share/texmf/tex/context/third/pgf/utilities/t-pgffor.tex
/usr/share/texmf/tex/context/third/pgf/utilities/t-pgfkey.tex
/usr/share/texmf/tex/context/third/pgf/utilities/t-pgfmod.tex
/usr/share/texmf/tex/context/third/pgf/utilities/t-pgfrcs.tex