Since I downloaded macos big sur, I've got these white flashes in my 2017 macbook air screen every 10 seconds when I'm watching videos (both streaming and offline). I visited one of these fourms a couple of days ago and found out if I turn of screen time and restart, it would be alright. I can't lie, it was okay... for a day. And it got worse. Now it is distracting and this is my "work system". So, please help me.