/usr/share/doc/libincidenceeditorsng4-mobile/changelog.Debian.gz is in libincidenceeditorsng4-mobile 4:4.8.2-0ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/libincidenceeditorsng4-mobile/../libcalendarsupport4/changelog.Debian.gz