Web designer Joshua Maddux noticed that the Facebook app for iOS activated the camera as he flipped through the news feed.
Do not rush to build conspiracy theories. This is most likely a bug. Although he works on five proven devices with Joshua, he discovered some pattern.
So it looks in practice:
The designer found a flaw in iOS 13.2.2. In iOS 13.1.3, the camera did not activate, however, one of the users noted that it turns on in iOS 12.4.1 on the iPhone 7.
The Next Web claims that this only happens if the user gives the application access to the camera . Otherwise, iOS blocks the function.