====== Find and remove old and non-Ubuntu packages ======


<code>
current=$(lsb_release -cs)

for pkg in $(dpkg-query -W -f='${binary:Package}\n'); do
    if ! apt-cache policy "$pkg" | grep -q "$current"; then
        echo "$pkg"
        apt autoremove --purge "$pkg"
    fi
done
</code>

For each package, select ''y'' or ''n'' to remove it and any dependencies.