Hi, I'm experiencing the same issue and I've contacted Squarespace about this and they told me that it's something that they will be looking into in the future. It seems to be a bug... So annoying.
But you seem to have fixed it now? Did you? Or is it just that it happens to show fine for me?
I have the same issue here: yadiyada.se (it's listed as unsafe, it's going through the SSL process as we speak).
You can see it in the pink color as well as the black at the bottom. It just seems to happen on random and on certain displays...
Best,
Chris.