The tag is present in Lintian version 2.113.26. That is the most recent version we know about.
We use semantic versions.
The patch number is a commit step indicator relative to the
release tag in our Git
You can find the detection logic for this version at commit 43a81d7. For merge requests, please use the latest version in the Lintian check debian/debconf.
Packages using debconf in their preinst scripts must pre-depend on debconf.
Since debconf is usually installed already, that is better than depending on it but falling back to a different configuration system.