That's strange because it's kernel related so changing the build.prop has no effect as already mentioned, which I can +1 to.
I'll look again just to make sure, there might have been a placebo effect...
I noticed the behavior in the kindle app. When reading white text on a black background the screen got brighter when there was a white chapter start image.
I know this is for z1c, but I just got my hands on a z1 c6903 and it seems to do this a lot and fade on dark colours. I read that on 4.2.2 there used to be an optimized backlight option and disabling it would stop the screen doing it but it was taken out from kitkat. Does anyone know if any custom kernels would fix it? It's just really annoying.
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