With the move to EE, Blindness/Deafness has changed to where you can no longer target nor see other players or foes at all, while this is more true to the name, this does leave the player kinda just standing there chugging potions or running around hoping not to die. So, my suggestion is to put it back to how it used to be, where you could still see other players and foes in close proximity.
Wasn't aware there was a change in how the effects function between 1.69 and EE, but if there was, there's nothing we can do about it, I think.