Facebook Encryption

In March 2019, Mr Zuckerberg said he wanted the firm to make end-to-end encryption the base level of security for all its messaging services - including Facebook Messenger and Instagram messaging. But he did not lay out a timeline, and many engineers thought it would be several years before it happened.

The initiative would mean that messages - including text and imagery - are digitally scrambled so that only the sender and receiver can make sense of them, and not Facebook itself.

WhatsApp, which is owned by Facebook, already has this level of security.