A problem:
Chrome dims my screen, background or youtube video randomly without a reason

Then it simply dims the lightning of my chrome browser
when i try make screenshot, can not screenshot the dim, it stops dim

sometime i pause a youtube video, it dims

sometimes my background desktop starts to dim and undim 4times per sec, when scrolling in Chrome


nothing to do with:
chrome://extensions/Turn Off the Lights Chrome extension
not using this


Google never heard of my problem.

Any one know a fix? thx