Facebook’s tensions with advertisers predate the boycott

Prominent marketers' pullback is their most visible confrontation with Facebook, but not the first. Coca-cola, Adidas, Best Buy, Diageo and Chipotle are just some of the dominant brands who have stopped advertising on Facebook and Instagram through, at least, the whole month of July. The boycott has become one of the biggest protests against Facebook's handling of defamatory content on the platform, but as Sahil Patel and Nat Ives explore in The Wall Street Journal, the problems go back a long time.