Can't read the article, but I've seen a lot of my friends unfriend other people that have political opinions that differ from theirs. And the ever so popular po

Can't read the article, but I've seen a lot of my friends unfriend other people that have political opinions that differ from theirs. And the ever so popular post "If you disagree with thing xyz let me know know so I can unfriend you!" This isn't Facebook's doing. People self-select monocultures.