A very good article in (surprise) the NY Times. Basically someone appeared on Jeopardy! and did a gesture with three fingers. A mob of 600 former contestants signed a letter condemning the gesture as white supremacy and demanding to know why it wasn;t edited out.
Of course the gesture was not white supremacy. He had won three times and was signally the number three. He signalled two when he was on two wins and one when he had his first win. But even confronted with these facts, they would not back down. They still demanded he apologise for his gesture. Somehow the fact he had a photo of Frank Sinatra on his Facebook page was also relevant.