Some characters when spoken to will unnecessarily open up a dialogue box with you instead of having the text over their head in a speech bubble. Usually these will incorrectly display the player's avatar as well. Screenshots below of the mushroom scavenger one. There's also a female bandit inside the GMS compound's cafeteria who has this issue (when you pass the persuasion + intimidation checks to pacify the bandits). And I'm pretty sure, if memory serves, that the Praetorian officer who warns you to get back at the Faceless blockade in Core City has a similar issue.