/usr/share/texmf/ is in preview-latex-style 11.86-2ubuntu1.
This file is owned by root:root, with mode 0o755.
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/usr/share/texmf/tex/
/usr/share/texmf/tex/latex/
/usr/share/texmf/tex/latex/preview/
/usr/share/texmf/tex/latex/preview/prauctex.cfg
/usr/share/texmf/tex/latex/preview/prauctex.def
/usr/share/texmf/tex/latex/preview/prcounters.def
/usr/share/texmf/tex/latex/preview/preview.sty
/usr/share/texmf/tex/latex/preview/prfootnotes.def
/usr/share/texmf/tex/latex/preview/prlyx.def
/usr/share/texmf/tex/latex/preview/prshowbox.def
/usr/share/texmf/tex/latex/preview/prshowlabels.def
/usr/share/texmf/tex/latex/preview/prtightpage.def
/usr/share/texmf/tex/latex/preview/prtracingall.def