This is an older page I had in a partial vimwiki. I remember digging into what the command was doing to some extent at the time, but I’ll be honest, I have no idea the specifics of what this command is doing.
comm -23 <(apt-mark showmanual | sort -u) <(gzip -dc /var/log/installer/initial-status.gz | sed -n 's/^Package: //p' | sort -u)I did break it down to just:
apt-mark showmanual | sort -uThis is the important bit of the command.
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