/usr/share/doc/libxpm4-dbg/changelog.Debian.gz is in libxpm4-dbg 1:3.5.10-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libxpm4-dbg/../libxpm4/changelog.Debian.gz
/usr/share/doc/libxpm4-dbg/../libxpm4/changelog.Debian.gz