packages becoming virtual during jessie->stretch upgrades

[Andreas Beckmann <anbe@debian.org>]

Hi,

if anybody has some spare time, I would be interested in packages that
are real packages in jessie but virtual packages in stretch, and the
packages in stretch that depend (recommend) on the virtual package.

This can cause upgrade issues ... like #863890.

The package texlive-math-extra is one such example, and the packages
dblatex, cadabra, lhs2tex, sisu-pdf depend on it.


Andreas