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I just started the game and something feels really weird. I'm 99% certian that it's not an input lag or anything like that.

When I stop pressing a movement key after using it, the player charecter keeps moving in that direction for few seconds as if I keep pressing it. It's really strange and uncomortable.

Is it supposed to be like this ?

Note: I have the Steam version if it matters anything.
So, are you running or walking fast when this happens?

Because if that's the case, then it is likely because of the momentum of the sniper, just like would happen in real life; remember the games tries to be as real as possible, and I don't think you can do something about it other than moving slower instead of faster.