/usr/share/doc/libidzebra-2.0-mod-grs-regx/changelog.Debian.gz is in libidzebra-2.0-mod-grs-regx 2.0.59-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libidzebra-2.0-mod-grs-regx/../libidzebra-2.0-0/changelog.Debian.gz