Aptitude erroneously thinks many packages are unused and wants to remove them.
Inspired by the advice on this group and the -s option, I'm trying out
aptitude. But I'm surprised by this:
$ aptitude -s upgrade
Reading Package Lists... Done
Building Dependency Tree
Reading extended state information
Initializing package states... Done
Reading task descriptions... Done
The following packages are unused and will be REMOVED:
followed by a long list of packages, some of which I'm running right now.
How does aptitude determine this list, and what's the best way to correct