/usr/share/doc/libjson-glib-dev/changelog.Debian.gz is in libjson-glib-dev 1.4.2-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libjson-glib-dev/../libjson-glib-1.0-0/changelog.Debian.gz