Windows, tiles.
Not only are bandits non-aggressive but killing them also yields huge negative morale because the player “kills an innocent”. This makes the second refugee center mission rather unpleasant (= kill 3 bandits).
Will be fixed as a part of https://github.com/CleverRaven/Cataclysm-DDA/pull/18840
I ran into this too. Moreover, I discovered that if I set them on fire while standing to their South-East, they yell at me to move until they die even though every other direction is unblocked.