SOLVED: ‘apt-get dist-upgrade’ error when going from Debian 9.x (“stretch”) to 10.0 (“buster”).
Thanks to user lamayonnaise in this Reddit, I was able to solve the problem described below, which I encountered when upgrading a Debian GNU/Linux box from old stable (9.x, a.k.a. "stretch") to new stable (10.0, a.k.a. "buster"). I've also seen this when upgrading from 'stable' to 'testing' — presumably the solution below would work there too.
Here's what the problem looks like — full transcript, out of consideration for search engine indexes:
root# apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
...