A new rule proposed by U.S. Customs and Border Protection (CBP) could require Canadian residents who are not citizens of Canada to divulge their social media history before they can enter the United States. Under the proposed change, listed as “mandatory social media,” anyone applying for ESTA (Electronic System for Travel Authorization) would be required to provide five years of social media history. Rosanna Berardi, an immigration expert in Buffalo, N.Y., told National Post that the change will not affect Canadian citizens with a valid passport, since they do not require an ESTA...