First guess. Fake. Pretend that Jew vs Jew is a thing that happens.
Second guess. Did Facebook respond with a big Fuck You Soros? I dunno. But somehow this story is somehow about Facebook being anti semitic? When all Facebook did was recognize that people hate Soros and point out that the AF protesters were tied to Soros, who people hate. There's no antisemitism at all there. Soros sucks. Many hate him. It's not antisemitic to say Soros sucks.
It's a way to challenge the whole idea of criticizing Soros with Facebook not fighting back.