Dear sslh maintainer,

sslh declares a constraint on the allowed versions of debconf. This
constrained version is extremely old and thus not needed. More
importantly, its presence blocks `dh_installdebconf` from adding to
`${misc:Depends}` the proper set of dependencies needed to support
debconf-2.0/cdebconf.

A MR that fixes this issue is available at:

https://salsa.debian.org/debian/sslh/-/merge_requests/4

Regards,