/usr/share/gtk-doc/ is in libjson-glib-doc 0.16.2-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/gtk-doc/html/
/usr/share/gtk-doc/html/json-glib/
/usr/share/gtk-doc/html/json-glib/JsonBuilder.html
/usr/share/gtk-doc/html/json-glib/JsonGenerator.html
/usr/share/gtk-doc/html/json-glib/JsonParser.html
/usr/share/gtk-doc/html/json-glib/JsonPath.html
/usr/share/gtk-doc/html/json-glib/JsonReader.html
/usr/share/gtk-doc/html/json-glib/annotation-glossary.html
/usr/share/gtk-doc/html/json-glib/ch01.html
/usr/share/gtk-doc/html/json-glib/ch02.html
/usr/share/gtk-doc/html/json-glib/ch03.html
/usr/share/gtk-doc/html/json-glib/ch04.html
/usr/share/gtk-doc/html/json-glib/home.png
/usr/share/gtk-doc/html/json-glib/index.html
/usr/share/gtk-doc/html/json-glib/index.sgml
/usr/share/gtk-doc/html/json-glib/ix01.html
/usr/share/gtk-doc/html/json-glib/ix02.html
/usr/share/gtk-doc/html/json-glib/ix03.html
/usr/share/gtk-doc/html/json-glib/ix04.html
/usr/share/gtk-doc/html/json-glib/ix05.html
/usr/share/gtk-doc/html/json-glib/ix06.html
/usr/share/gtk-doc/html/json-glib/ix07.html
/usr/share/gtk-doc/html/json-glib/ix08.html
/usr/share/gtk-doc/html/json-glib/json-advanced.html
/usr/share/gtk-doc/html/json-glib/json-base.html
/usr/share/gtk-doc/html/json-glib/json-glib-Boxed-Types-Serialization.html
/usr/share/gtk-doc/html/json-glib/json-glib-GObject-Serialization.html
/usr/share/gtk-doc/html/json-glib/json-glib-JSON-Array.html
/usr/share/gtk-doc/html/json-glib/json-glib-JSON-GVariant-Integration.html
/usr/share/gtk-doc/html/json-glib/json-glib-JSON-Node.html
/usr/share/gtk-doc/html/json-glib/json-glib-JSON-Object.html
/usr/share/gtk-doc/html/json-glib/json-glib-Serializable-Interface.html
/usr/share/gtk-doc/html/json-glib/json-glib-Versioning-information.html
/usr/share/gtk-doc/html/json-glib/json-glib.devhelp2
/usr/share/gtk-doc/html/json-glib/json-glib.html
/usr/share/gtk-doc/html/json-glib/json-streams.html
/usr/share/gtk-doc/html/json-glib/json-tools.html
/usr/share/gtk-doc/html/json-glib/left.png
/usr/share/gtk-doc/html/json-glib/license.html
/usr/share/gtk-doc/html/json-glib/right.png
/usr/share/gtk-doc/html/json-glib/style.css
/usr/share/gtk-doc/html/json-glib/up.png