> I needed to install a version of sendmail from testing a while back to
> test it.
Downgrading Debian packages is not well supported, by and large.
So installing `testing` packages into a `stable` install is manageable
(tho it itself can bring trouble) but going back to `stable` afterwards
tends to be a lot more complicated.
Transitions like the t64 transition going on right now in `testing` make
it yet more troublesome.
I recommend the use of snapshots when you want to try such a thing with
the intention of "going back" later.
> # apt install -t=bookworm db-util db5.3-util libc-bin libc-dev-bin
I can never remember exactly what `-t` really does, but I suspect you'll
need things like
apt install libc-bin/bookworm
to state more explicitly what you want.
Maybe you can do something like
apt install $(apt-show-versions | sed -n 's|/testing.*|/stable|p')
- Stefan
