What should happen: when an enemy is shot with a weapon using the Cryo Ammo power they may freeze and fall over. If they are not killed they will eventually thaw and get back up of their own accord.
What happens: the enemy thaws visually but they remain stuck lying on the ground.
Moving the enemy (by shooting/meleeing them or bumping into them, for example) will trigger them to get up. This can be a more serious issue in areas where all enemies must be defeated to proceed if the frozen enemy falls in an inaccessible area, such as behind cover on a ledge or on the other side of the bridge in Dossier: Archangel.
This is on Xbox One.
Having just started Legendary Edition's ME3 I can confirm that this issue is present in that game as well. It was not present in the original ME3 either.
I noticed this in ME3 as well. Enemies affected by singularity (or blasted by a detonation) can end up prone on the ground. They freeze in place and just continuously play impact grunts.
They stay there permanently until taking damage (often they end up behind cover, so you have to hunt for them just to end the encounter).
This was on PC, so it's not an issue specific to Xbox.
