post_install() {
    if ! getent group lightdm &>/dev/null; then
        groupadd -g 620 lightdm
    fi

    if ! getent passwd lightdm &>/dev/null; then
        useradd -c 'Light Display Manager' -u 620 -g lightdm -d /var/lib/lightdm -s /usr/bin/nologin lightdm
    fi

    passwd -l lightdm > /dev/null

    systemd-tmpfiles --create /usr/lib/tmpfiles.d/lightdm.conf
}

post_upgrade() {
    post_install
}