I have uploaded a NMU fixing this bug, a debdiff is attatched. Per the NMU guidelines since this RC bug is 7 days old with no maintainer response I have uploaded the NMU without delay.
diff -Nru ntopng-3.8+dfsg1/debian/changelog ntopng-3.8+dfsg1/debian/changelog --- ntopng-3.8+dfsg1/debian/changelog 2019-01-26 08:36:22.000000000 +0000 +++ ntopng-3.8+dfsg1/debian/changelog 2019-02-04 01:10:39.000000000 +0000 @@ -1,3 +1,10 @@ +ntopng (3.8+dfsg1-2.1) unstable; urgency=high + + * Non-maintainer upload. + * Add build-depends on libssl-dev (Closes: 920648) + + -- Peter Michael Green <plugw...@debian.org> Mon, 04 Feb 2019 01:10:39 +0000 + ntopng (3.8+dfsg1-2) unstable; urgency=medium * Fix missing space in postinst migration script (Closes: #920281). diff -Nru ntopng-3.8+dfsg1/debian/control ntopng-3.8+dfsg1/debian/control --- ntopng-3.8+dfsg1/debian/control 2019-01-22 01:55:35.000000000 +0000 +++ ntopng-3.8+dfsg1/debian/control 2019-02-04 01:10:39.000000000 +0000 @@ -27,6 +27,7 @@ python3-breathe, python3-sphinx, python3-sphinx-rtd-theme, + libssl-dev, Standards-Version: 4.3.0 Homepage: http://www.ntop.org/products/ntop/ Vcs-Git: https://salsa.debian.org/debian/ntopng.git