Description
The postinst script handles the system startup procedure: if systemd is present, /etc/init.d/openhab is removed.
This is a bug for several reasons:
a) if a system reverts from systemd to sysv strartup openhab will not automatically be started because you deleted the startup file
b) debsums reports the missing config file which is very annoying (I execute debsums daily in a cron-job to check for such missing files and receive this error daily until I manually fix it
c) This behaviour is forbidden by the debian policy (see section 10.7.3 about behaviour with configuration files and section 6.2. about maintainer scripts idempotency).
proposed solution:
just leave /etc/init.d/openhab in place even on a systemd (why do you remove it in the first place?)