Hello. When you enable HDR for games and applications on the Intel graphics adapter in the system settings, the colors fade and the screen appears to become less bright. this is normal?
Go to Control Panel > Hardware and Sound > Power Options, then click on "Change plan settings" next to your active power plan. Click on "Change advanced power settings." Scroll down to Display, then under Enable adaptive brightness, switch it off for both the battery and plugged in modes.
I have Adaptive Brightness disabled and I still see a washed out effect. My understanding is that you should only turn this on if/while using games or apps with support for the feature.