In leaked memo to advertisers, Facebook's top ad exec promises an external audit of its safety tools and practices and tries to talk fleeing advertisers off the ledge

· In a new memo sent on Friday, Facebook's VP of global marketing solutions Carolyn Everson assured advertisers that the company is serious about addressing the major concerns of civil-rights groups leading a boycott of the platform to protest hate speech and divisive content.
· Everson said that the company was committing to...