Okay, so I've had an issue my last mission, where half a pod just didn't move when I activated them. I did not have any units concealed when it happened.
Two aliens did their normal scramble move, and went to cover, but two of them just stayed behind. One was a demolitionist, who just stood out of cover like an idiot, and the other was a drone, who I think was affected too because it just didn't move at all.
Is this an issue with the base game? I never had it happen to me before.
The only mods I have installed come from the recommended list, plus some cosmetic mods.