/usr/share/help/de/zenity/calendar.page is in zenity-common 3.8.0-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/help/de/zenity/../../../help-langpack/de/zenity/calendar.page
/usr/share/help/de/zenity/../../../help-langpack/de/zenity/calendar.page