If it looks like a duck, and quacks like a duck, we have at least to consider the possibility that we have a small aquatic bird of the family Anatidae on our hands.
Antisemitism is not exclusive to Nazism at all. This is a news article. They don't just write things for no reason. They wrote "Antisemitic slurs" because they saw Antisemitic slurs.
Perhaps you meant to reply to a different comment. I was responding to the previous commenter's apparent attempt to explain-away antisemitic slurs as mere "be[ing] edgy" rather than being indicative of antisemitic belief, not trying to specifically nail down this alleged leaker's specific political affiliations.