I am posting this here as much for my own benefit as anyone else - at least I'll know where to find it again!!
An issue I have come across recently regards the removal of Firefox type browsers from a system. If you decide to run a single browser and remove all others it should be an easy case of "apt-get remove <app>", unless it is a Firefox derivative. Sometimes you will get a response along the lines of - "removing Iceweasel, installing Icedove". What??
It turns out that there will be a dependency somewhere in the system that needs a Firefox type app to keep it happy. Sometimes that dep may even be broken but it still needs its friend! To find the culprit, and using Iceweasel as our example, instruct apt-get thus -
apt-get purge iceweasel -o Debug::pkgProblemResolver=1 -s
In one instance I had "sun-java6-plugin" identified. Someone else I read about had a broken Finnish spell checking plugin at fault! Anyway, once the dep is identified it can be removed, and then the target app can also be removed. Of course, this "error " is not purely the domain of Firefox - I'm sure there are other examples out there.
I hope this helps with the sometimes baffling "errors" that can be randomly thrown up! There is a lot more to this apt-get caper than I was aware of.
