preinst is in ubuntu-docs 18.04.3.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 | #! /bin/sh
set -e
if [ "$1" = upgrade ] && dpkg --compare-versions "$2" lt "11.10.1" ; then
update-alternatives --quiet --remove-all firefox-homepage || true
fi
exit 0
|