Today a new answer was posted on Can't start a numbered list on a number other than 1. The issue seems to have been fixed since 2014 by default on all sites.
This makes the issue described in the question not reproducible anymore. In the question itself, there is a line trying to demonstrate the problem which currently doesn't make much sense:
- this should be a 2. not a 1. as I wrote 2. but it changes automatically to 1.
If that is not the definition of "not reproducible" I don't know what is...
Why was my flag on this question declined?