Users of Robinhood say they are unable to trade high-flying stocks, including GameStop and AMC, with a notice saying the stocks are “not supported” on Robinhood (Maggie Fitzgerald/CNBC)

Facebook adds opt-in biometric fingerprint, face, or iris scan authentication for WhatsApp on desktop or web  —  WhatsApp, the Facebook-owned popular messaging app with more than 2 billion users, has been getting a lot of heat and losing users in recent weeks after announcing (and then delaying) changes to how it uses your data.