Dead pixel? Question for retina owners

I've run full screen pixel tests and have never noticed it before, but search youtube for one of those many comicon interviews (or anything with black bars). In chrome canary do full screen and look at the bottom left---there is a bright white pixel at the very bottom left corner. It does not appear in safari or in any other instance except youtube on canary. As stated earlier, this white pixel does not appear in full screen dead pixel tests in either the black or white screens.

I used the LCD test here: http://www.ekimsoftware.com/products/lcdtest/