Enable unattended upgrades
It seems the unattended upgrade was/is no configured.
Check and enable this
Simply installing unattended-upgrades
might work
putting /usr/bin/unattended-upgrade
into /etc/cron.daily
does not upgrade e.g. chrome
.
See https://askubuntu.com/questions/64318/how-can-i-enable-silent-automatic-updates-for-google-chrome
Edited by Martin Koehler