Black Lives Matter transferred millions to a Canadian charity run by the wife of its co-founder to purchase a sprawling mansion that had once served as the headquarters of the Communist Party, public records show. M4BJ, a Toronto-based non-profit set up by Janaya Khan and other Canadian activists, snagged the 10,000 square foot historic property for the equivalent of $6.3 million in cash in July 2021, according to Toronto property records viewed by The Post.