how can I prevent full screen videos?

[jgreg02]

Galaxy S9+ , Android 8.0.0, some apps and web pages start playing full screen videos at the worst possible times and they won't stop with close screen.

CNBC app is one that does this.

How do I prevent this from happening and once it does turn it off Fast?

 

[Jimmy Le1]

Go to settings>display>Full screen app .. Uncheck it ..!!