If I remember this particular event around the Fox website, they (Fox) were furiously trying to remove those offensive posts in real time, but were simply unable to avoid having many of them captured by others, and stored permanently for the world to see.
What Fox did, in my opinion, was open their back doors, and show the world exactly who they are, and what they support. And this is not something that surprises me at all. Even though not all Fox readers/viewers espouse this type of hate, they effectively do by closing their eyes to the true hatred that was aroused by the existence of Fox, and it's demographic.
We need disagreement in the public sphere and especially through media. But to garner and support genuine hatred at this visceral level, and pretend that it is benign, or unworthy of their open condemnation, Fox has revealed it's true nature.