/usr/ is in preview-latex-style 11.91-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/doc/preview-latex-style/
/usr/share/doc/
/usr/share/
/usr/share/bug/
/usr/share/bug/preview-latex-style/
/usr/share/bug/preview-latex-style/presubj
/usr/share/doc/preview-latex-style/README
/usr/share/doc/preview-latex-style/README.Debian
/usr/share/doc/preview-latex-style/changelog.Debian.gz
/usr/share/doc/preview-latex-style/copyright
/usr/share/doc/preview-latex-style/preview.pdf
/usr/share/doc-base/
/usr/share/doc-base/preview-latex-style
/usr/share/texmf/
/usr/share/texmf/doc/
/usr/share/texmf/doc/latex/
/usr/share/texmf/doc/latex/preview/
/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
/usr/share/texmf/doc/latex/preview/preview.pdf