by Bobbolo Faraglia
When you open pokemon go, your screen resolution will be lowered to HD (for better performance) and the status bar will disappear (immersive mode).
When you close pokemon go, the status bar will be back and the resolution will be set to FullHD.
If you want to lower further the game resolution, or if you want to have a higher resolution when the game is closed, simply change the values in the shell command blocks (HD=720x1280; FHD=1080x1920;QHD=1440x2560).
If you want to hide the navigation bar, add a block with the following command: settings put global policy_control immersive.navigation=*
This will disable heads up notifications during game due to some display errors. Let me know if it works.