When using the Obelisk to open a greater rift, when clicking on the greater rift difficulty drop down, your mouse will click through the UI and on to the background, making you run away and have to do it again. This is infinitely repeatable if you just do not move your mouse on the drop down and open then close it, then try to open again. If you don’t move your mouse when closing the drop down, it wont actuate as if you are selecting the menu at all and click the game screen instead, making you run off.