Hi Oleg,I'd say the best way to handle this would be to work with the package maintainer/upstream to allow config files to be specified in /usr/share/<package>. This way dpkg will automatically remove the files for you.
Before going down that path I did attempt it in /etc/. It was messy but the closest thing to a working solution was manually calling `mv_conffile` in the postrm script. See https://salsa.debian.org/Mobian-team/miniramfs/-/merge_requests/7/diffs for an example.
