NEW YORK (AP) ??" Social platforms have learned to remove violent videos of extremist shootings more quickly over the past few years. It's just not clear they're moving quickly enough. Police say that when a white gunman killed 10 people and wounded three others ??" most of them Black ??" in a "racially motivated violent extremist" shooting in Buffalo Saturday, he livestreamed the attack to the gaming platform Twitch, which is owned by Amazon. It didn't stay there long; a Twitch spokesperson a...