That is very odd.. So we're talking about that black 1-pixel high line on the very bottom of the screenshot?
And you're saying that's not something that is in your actual image at the time of capture -- and that it spontaneously appears when you add the square/circle highlight annotations?
I am not unable to reproduce it here -- can you walk me through the process that leads to it, and give me some more details about when it appears and any clues you can discover about what triggers it?
Anyone else seen this happen to them?