Stack Exchange sites are often discussed with names ending in
.SE. This happens to be the top-level domain name for Sweden, a very popular TLD locally. It's really bad when saying SU.SE because that is one of the largest Swedish universities and the abbreviation of "Superuser" may not be apparent to everybody.
I have started to learn this now but I suspect new users may get confused. My suggestion is that we avoid saying
Superuser.SE and similar to people at the SO site, especially to new users, but just use the correct name
It is hard to find examples from real comments, but here are some from Meta: