Debian Apt AutoremoveBy Dag, on December 29th, 2016
Usually you'll use the autoremove functionality to clean up packages no longer needed. But IF you DO want to keep those packages but don't wanna see the nag about it every time you perform an apt-get install, you can clear the autoremove status from packages with aptitude:
# aptitude keep-all
Now it won't show the packages anymore. This can be handy if you've messed around so much that you're not sure about dependency and not sure if you actually need them or not. A few kB or even MB extra won't hurt anyone. This is not something you'll do very often, and if it can save a world of hurt and ease of management, it's often worth it.