Could you please try to build the minimal-package from source code and attempt to install it?
Posted it here a while ago:
ppc64 architecture
Expected outcome:
/var/lib/dpkg/info/minimal-pacakge.postinst: line xx: xxxxx Aborted
But then we have something simple enough to be able to contact the APT developers. Then no need to mention any of the complexity of Whonix, dist-base-files, etc.