So paranoid 21st-century folk may not be entirely happy to hear about a 'bug' which turns on their phone's camera whilst they're using the Facebook app. The glitch affects iPhone owners, who said their camera suddenly switched itself on while they were scrolling through their feed, watching videos or looking at photos. When people turned the video to full-screen mode and then switched back to Facebook's normal view, they could see a little open space on the left and the camera app in the background. Several people have tweeted about the bug and it has been replicated by tech journalists. Daryl Lasafin, a creative director, tweeted: 'Facebook app on iOS 13.2.2 opens my phone's rear camera when I open a profile photo swipe down to return (look at the little slit on the left of the video). Is this an app bug or an iOS bug??'