Missing dependencies for package `forest`, `environ`

[Karl Berry]

Indeed, as has been said many times before, and no doubt will be many
times more, TeX Live is not an operating system and we are (at least I
am) not going to introduce every conceivable kind of
dependency. Especially since sometimes the dependency cannot be
determined until runtime, so no full solution without dynamic loading is
possible. Let alone compatibility issues, which are really impossible to
determine.

What's relevant for TL, as I've said, are hard/100%-always-required
dependencies. I don't want to list engine-dependent or
anything-else-dependent dependencies except as "soft", which are just
for documentation, as I wrote in the description on pkgcontrib.html.

Other than that, people who choose to do a "minimal" installation will
just have to put up with installing the optional dependencies that they
wish to use themselves. That's life. --best, karl,