/usr/share/doc/oxideqt-codecs-dbg/changelog.Debian.gz is in oxideqt-codecs-dbg 1.0.0~bzr501-0ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/oxideqt-codecs-dbg/../oxideqt-codecs/changelog.Debian.gz