/usr/share/doc/irssi-plugin-otr-dbg/changelog.Debian.gz is in irssi-plugin-otr-dbg 1.0.0-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/irssi-plugin-otr-dbg/../irssi-plugin-otr/changelog.Debian.gz