I notice in iOS, often times when I open an app, such as YouTube, the first thing that it shows is a screenshot of that app from one of the more recent things I was doing with the app.
When I multitask back to the app, the OS loads these images before the app is fully running and able to process input.
But it strikes me as useless, since the buttons on the app don't even function at that stage, and it even does this for apps that don't fully restore state so you see it go back to a main screen after showing you what you were doing in the app before. It's also a security concern because I could be writing in a password-protected note or something and it shows up briefly when opening the app, or an old YouTube video screenshot could show up when I'm opening the app.
How can this "featured" be turned off in iOS.