Incorrect box around targetable objects while the cursor is on top of them.
I think it is really visual in the image (http://prntscr.com/5ai0af). Here are other examples (http://prntscr.com/5ai0ln) (http://prntscr.com/5aqnjh). It doesn't happens to my friends in the actual patch 4.20. Champions, minioms, monsters, wards, turrets... with every targetable object, but only occasionaly. There are random gaps that doesn't fill with the box, and they have the form of other objects, or just part of them. If you need information, just ask me for it.