I've read that Pope Pius X counted Jews as some of his best friends. The Herzl meeting is often used as evidence of Pope Pius X's very Catholic attitude toward Jewry.
The mistress of Mussolini Incredulous references is not Margherita Sarfatti, another of Mussolini's mistresses.
Margherita Sarfatti was born Margherita Grassini, in Venice, the daughter of Amedeo Grassini and Emma Levi. Amedeo was a wealthy Jewish lawyer and businessman. He was a fiscal attorney for the Venetian government and a close friend of Giuseppe Melchiorre Sarto, later Pope Pius X. He would later be made a Knight of the Order of the Crown of Italy.
I prefer that a canonized pope had had zero Jewish friends.