On darker backgrounds (but not completely black) such as dark grey, dark red there are a lot of horizontal scan lines with a bit darker tone. They are hard to see from normal viewing distance (they absorb into the background), but when I increase the brightness or look on the screen from close distance they are clearly visible. On white background there is no way to see them.
I took a few photos (they are a bit exaggerated) and marked those lines with arrow. Please ignore that discoloration around the edges as it's mostly glow. I've updated firmware. Firstly thought that it's a problem with cable or GPU, even tried lowering refresh rate but it didn't help and I realized that it happens also when monitor is disconnected from GPU, so it seems to be a problem with panel.
https://imgur.com/a/9UhrFJD
The question is - is it normal for that type of panel (big curved IPS) or should I RMA it?