Well. To avoid black screens/blue flickering, you have to Disable HW overlays in Developer Settings, every time reboot the device. you can download this script
https://forum.xda-developers.com/att...3&d=1399997136 to make permanent this setting.
1) Unzip the script
2) Put the script in /sbin/.core/img/.core/post-fs-data.d (you have to install Magisk First)
3) chmod 777 the script file
4) reboot and check in developer settings if Disable Hw overlays checkbox if active !