/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/ is in libjs-mathjax-doc 2.7+20171212-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/CommonHTML.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/HTML-CSS.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/MMLorHTML.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/NativeMML.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/PlainSource.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/PreviewHTML.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/SVG.rst.txt
/usr/share/doc/libjs-mathjax-doc/html/_sources/options/output-processors/index.rst.txt