What is the grey box and how can I get rid of it??
I have a grey box appear in all apps and when touched it show a Maximize symbol, a Puase symbol and a cancel symbol.
what is it? And how can I remove it??
iPad Pro Wi-Fi, iOS 12
That's Picture-In-Picture (https://help.apple.com/ipad/12/#/iPad3e67c9c1), it's one of the multitasking features that lets you watch a video whilst using another app.
What happens when you tap the maximise icon (the left-most of the three) or the close icon (the 'x') ? What apps show one on the multitasking screen, could it be from one of them ?