/usr/share/doc/libxfixes-dev/changelog.Debian.gz is in libxfixes-dev 1:5.0.3-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libxfixes-dev/../libxfixes3/changelog.Debian.gz
/usr/share/doc/libxfixes-dev/../libxfixes3/changelog.Debian.gz