Just wanted to point this out in advance of protestants coming around and fulminating that the title is blasphemous.
Of course, the Popes of Alexandria, like the Popes of Rome and the Patriarchs of Antioch, all can rightly claim petrine foundations for their sees: Antioch and Rome because St. Peter occupied the see, Alexandria because he consecrated his secretary, the Evangelist Mark, to be its first bishop.
I will fulminate only to the extent of offering lightning-quick thanks for this interesting information.