that's a fun one
during the main quest you fight through greenetech genetics to kill a courser and etc, when you reach the top of the building, there is a scene that plays with said courser and some gunners: the courser is asking for a password to open a locked door and the gunners tries to negotiate with him to no avail, the courser simply kills all of them
except sometimes this is not what happens
sometimes the gunner can spawn using heavy combat armor (especially if you are doing this quest at a high level), so as a highly armored npc, the courser using an institute pistol simply cannot do enough damage to kill him - so the dialogue scene does not continue. The courser shoots once, the gunner don't die and the scene become stuck. I confirmed this by selecting the gunner held at gun point, and using the console unnequiped all his armor, then the courser pistol does enough damage killing him and the scene continues as expected.
Issue Data
Issue #29458: Courser and Gunner dialogue can become stuck