After upgrading my LG G6 to Oreo, I notice that not all apps are listed in the App Scaling settings. Before Oreo I'm pretty sure I could change the scaling for any app, but now it's just a select few. I have a few games that no longer display properly because of this.
I do have the "Game Tools" icon turned on, but it does not offer the App Scaling option ("Go full screen") in all apps. In fact, in most of my games it only offers "Take a break," "Take a screenshot," and "Adjust game graphics." That last one only has Resolution and Frame rate settings, not app scaling.
It looks like the only apps that have "Go full screen" available in the Game Tools are the same apps that can be adjusted in the phone's App Scaling settings.
So, how do I change the app scaling for these games that no longer display properly?