[tex-live] When is a package removed from TeX Live?

[Leo Liu]

Hello all,

Every time I update TeX Live using tlmgr, there are some new packages, and
some old packages are removed as well. slashbox and showdim are removed last
time, for example. It is necessary to select some packages from thousands of
them to put into TeX Live, but sometimes it makes an old document
uncompilable. Although there are more and more packages in TL, it seems there
are still enough space to put all compressed packages into a DVD, I wonder
when is a packages removed from the TeX Live source, and how can I rely on it.
Thanks.

Leo Liu