Signal takes a jab at Facebook: Here’s what it said

The encrypted messaging company Signal has long been popular with activists, investigative journalists, politicians and assorted law enforcement officials because of its emphasis on privacy and security. Its growth was steady—but slow. Then came Christmas break. Employees returned from the holidays to an unexpected surge in new users that overwhelmed Signal’s servers and sent engineers racing to increase capacity.

The catalyst was a backlash against rival WhatsApp, which announced an updated privacy policy that included sharing some user account details with its parent company, Facebook Inc., turning off some of its 2 billion-plus users. Tesla Inc. Chief Executive Officer Elon Musk helped stoke the exodus, encouraging his army of Twitter followers to “use Signal.”