/usr/share/gtk-doc/ is in libxml2-doc 2.9.3+dfsg1-1ubuntu0.6.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gtk-doc/html/
/usr/share/gtk-doc/html/libxml2/
/usr/share/gtk-doc/html/libxml2/general.html
/usr/share/gtk-doc/html/libxml2/home.png
/usr/share/gtk-doc/html/libxml2/index.html
/usr/share/gtk-doc/html/libxml2/left.png
/usr/share/gtk-doc/html/libxml2/libxml2-DOCBparser.html
/usr/share/gtk-doc/html/libxml2/libxml2-HTMLparser.html
/usr/share/gtk-doc/html/libxml2/libxml2-HTMLtree.html
/usr/share/gtk-doc/html/libxml2/libxml2-SAX.html
/usr/share/gtk-doc/html/libxml2/libxml2-SAX2.html
/usr/share/gtk-doc/html/libxml2/libxml2-c14n.html
/usr/share/gtk-doc/html/libxml2/libxml2-catalog.html
/usr/share/gtk-doc/html/libxml2/libxml2-chvalid.html
/usr/share/gtk-doc/html/libxml2/libxml2-debugXML.html
/usr/share/gtk-doc/html/libxml2/libxml2-dict.html
/usr/share/gtk-doc/html/libxml2/libxml2-encoding.html
/usr/share/gtk-doc/html/libxml2/libxml2-entities.html
/usr/share/gtk-doc/html/libxml2/libxml2-globals.html
/usr/share/gtk-doc/html/libxml2/libxml2-hash.html
/usr/share/gtk-doc/html/libxml2/libxml2-list.html
/usr/share/gtk-doc/html/libxml2/libxml2-nanoftp.html
/usr/share/gtk-doc/html/libxml2/libxml2-nanohttp.html
/usr/share/gtk-doc/html/libxml2/libxml2-parser.html
/usr/share/gtk-doc/html/libxml2/libxml2-parserInternals.html
/usr/share/gtk-doc/html/libxml2/libxml2-pattern.html
/usr/share/gtk-doc/html/libxml2/libxml2-relaxng.html
/usr/share/gtk-doc/html/libxml2/libxml2-schemasInternals.html
/usr/share/gtk-doc/html/libxml2/libxml2-schematron.html
/usr/share/gtk-doc/html/libxml2/libxml2-threads.html
/usr/share/gtk-doc/html/libxml2/libxml2-tree.html
/usr/share/gtk-doc/html/libxml2/libxml2-uri.html
/usr/share/gtk-doc/html/libxml2/libxml2-valid.html
/usr/share/gtk-doc/html/libxml2/libxml2-xinclude.html
/usr/share/gtk-doc/html/libxml2/libxml2-xlink.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlIO.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlautomata.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlerror.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlexports.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlmemory.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlmodule.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlreader.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlregexp.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlsave.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlschemas.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlschemastypes.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlstring.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlunicode.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlversion.html
/usr/share/gtk-doc/html/libxml2/libxml2-xmlwriter.html
/usr/share/gtk-doc/html/libxml2/libxml2-xpath.html
/usr/share/gtk-doc/html/libxml2/libxml2-xpathInternals.html
/usr/share/gtk-doc/html/libxml2/libxml2-xpointer.html
/usr/share/gtk-doc/html/libxml2/libxml2.devhelp
/usr/share/gtk-doc/html/libxml2/right.png
/usr/share/gtk-doc/html/libxml2/style.css
/usr/share/gtk-doc/html/libxml2/up.png