Please correct me if its the apps that dont fully support the 19:9 ratio or its the problem from nokia's end.
For instance sometimes during facebook use i can see something running in the background in the notch extended part of the screen e.g. a story that i openned in Facebook and the phone goes to looking like a 2 rupee phone.
When sending a snap on Snapchat the picture in the notch extended part gets cut out!!!