When you have an idea about it, the separation of the independent build
from the binary has not worked out. These dependencies now happen to
be required for every platform, but should just be required for the
arch-independent builds:

  Build-Depends-Indep: texlive-latex-base, texlive-latex-recommended, texlive-science, texlive-latex-extra, texlive-humanities

Many thanks for any suggestion

The fix for #620999 is not right. I had disabled the threading on the kfreebsd platforms to work around the compilation problem with threading.

Steffen