Known and not considered a bug as such. Or if it is, it should be covered by this shortlist item:
- BHV Nation Overview & Scouting Reports It used to be that in Dom2 spies were able to see the sites of the province they were in. This is not possible anymore (they just see the icons). However, if you lay siege to an enemy castle, you will be able to see the sites in that province fully through the Nation Overview screen. Is this WAD due to the nature of the F1 screen and the special situation of sieges?
I tested this to some degree at one point when I was investigating it. It's a minor glitch at best.