button cart clear com firefox opens pressed product results suggestions testing try working

When the "Go to Cart" button is pressed and the cart opens at e-junkie.com I get different results from FireFox vs. IE.
IE does it right - one product, but Firefox says two (same product, just two of them". Suggestions?

That's only because you'd have been testing with another product. Clear your cart and try again and you'll see it's working fine.