I was watching a video of Dragonborn and the player was using Nord Hero Arrows. I remember that you could not make these before and was hoping that if they added them that they fixed the problem with improving the Nord Hero Bow.

Are Nord Hero Arrows added in Dragonborn or Dawnguard?

Do you know if the glitch preventing improvement of the Bow has been fixed along with the addition of the arrows?

Your answers are appreciated.