Sorry, I’m not sure whether this is a proper place to ask this question, but I can’t find a better place.
I am not a discourse host/owner. I am just on a forum powered by Discourse. I have sent some private information to a friend on the forum using the “Private Message” feature.
The information is safe for the friend and me, but I don’t want the forum owner to know anything about it. Do I need to worry about this?
I think it’s possible. In almost all communities (not just Discourse) this is. But usually I say that if you do not trust the administration, then you should not be on this forum.
Usually the administration does not read personal messages, there’s just no time.
There are more important things in the community to do than spy on members. The Internet is generally not a very confidential place. But the Discourse team is doing its best to keep such issues to a minimum.
If they know how to write an SQL query (or know someone who does) they can use the data explorer plugin to retrieve any information from the database, including PM’s.
So is there a link on your profile for admins to read your messages? No. (EDIT: yes apparently there is)
Does it take a skilled person more than 5 minutes to get to your messages? Also no.
Yes the admins can read your messages, and contrary to what @michaeld said, yes there is a direct link on your profile for them to click. The exact same link you see on your own profile in fact.
They have a messages option where they can look at messages. However, admins should not be looking at messages. Also, if you don’t trust the admins on this forum you are one you shouldn’t be on it at all.