Confirming this is still going on. Just as the others mentioned. You can run your cursor along the edge of the screen between the two monitors and double-click to have it release from game and shoot over to your other monitor (having the mouse dragging that direction while you’re clicking). Very annoying bug and leads to death by enemy or running off something. Surprised it has been around for so long and still there – Blizzard wouldn’t leave things like this around for so long…