The head of New Jersey’s largest Catholic diocese was recently impersonated on social media by someone who opened an account in his name, Archdiocese of Newark officials said. Cardinal Joseph Tobin, who has led the archdiocese since 2017, was impersonated on Instagram, although the exact dates the imposter account appeared is unclear. “It happened on one social media platform, and we successfully addressed it with the site’s administrator,” said Maria Margiotta, the archdiocese’s director of communications. “In the event that someone was following that imposter account, we wanted to alert them…