Check the HiDPI Daemon in the Display setting…
This HiDPI Daemon is for switching between Intel video card and NVidia. On systems with different cards the program does nothing but interfere with the power management of the monitor.
What video card do you have? You might be able to remove the package.
Not at all what you’re looking for, but in case someone else finds this thread,nit does appear that PixelExperience has an official build.
https://get.pixelexperience.org/begonia
I haven’t used this ROM before. It is AOSP-based and comes with all the Google stuff. So, not wha OP wants…but at least no MIUI.