After accidentally removing /etc/postfix/main.cf on a 42.2 host, I tried to
revert to the "standard configuration", by running "zypper in -f postfix".

To my surprise, that reinstated an /etc/postfix/main.cf which is rather
different than the one present after the usual standard install.

The same happens when switching from postfix to sendmail and back again, which
of course also reinstalls the postfix package.

Especially disturbing, IMO, is that the reinstalled-package main.cf contains
"inet_interfaces = all", instead of the sane after-normal-installer default of
binding only localhost. Thus, such a package reinstall potentially opens
postfix to being remotely connected when it wasn't before.

Sorry if this is the result of some long standing policy - it surprised me, so
I thought it good to report...