Bug#222641: dpkg: [CONFFILE] should inform user when a conffile is not being replaced due to local deletion
Under these conditions the new version of the conffile should be
dropped in <path>.dpkg-dist, as is done for other local
modifications; and the proposed message should say that this has been
done. This makes it really easy for the admin to look at the new
version and decide whether they want it.
I have no idea whether this already happens. I looked in the manual
but couldn't find anything.