rear/rear — pull request #474 by Reiner030 (2014-10-13 17:34:11+00:00)
Title: https://www.debian.org/doc/manuals/maint-guide/dother.de.html#conffiles

=> The command to install the debian package (which automatically configures the conf files) was missing.
It autoselects all files in /etc as config file so conffiles can be empty (but must still exists).

man dh_installdeb
package.conffiles
This control file will be installed into the DEBIAN directory.

In v3 compatibility mode and higher, all files in the etc/ directory in a package will automatically be flagged as conffiles by this program, so there is no
need to list them manually here.