I can still see the square, but I didn't see it until you pointed it out. It's funny, I was just looking at this icon earlier today, and I never even noticed. It's pretty pixel perfect as of now, on a phone, you probably wouldn't even notice.
No problem! That's odd that you can't see it on your Mac though. I thought those things were like, made for design! You'd think they'd show everything! Who says PC's can't be better then Macs sometimes
Well would you look at that! I opened the page in Internet Explorer 9 (After 2 freezes and 3 or four popups ) and there was no square! I've actually seen this happen before, especially on dribbble. Well done on the icon, now that I can see it's flawless