Two days ago I bought a new 2020 iMac 27", i5 3,3 GHz 6‑Core, Radeon Pro 5300/4GB GDDR6, 40GB RAM and immediately updated to Big Sur 11.0.1 and Safari 14.0.1.
Watching Netflix movies in Safari the screen will start to flicker and then within a minute the screen mirrors into two exact halves. After quitting Safari I then realise that has also done the same with the finder desktop etc. And no, it isn't the window splitting function. I have exactly the same system OS and Safari on my work iMac 27", 2017 and tried to reproduce the exact scenario but no glitch.
I am specifying Safari in particular because the glitch doesn't happen, with the exact scenario using Firefox or Chrome on the effected iMac. I have attached two videos to better show what I am facing. I have not, even after scouring the internet and here, found any posts regarding this strange glitch.
Thanks for any information in advance.
Watching Netflix movies in Safari the screen will start to flicker and then within a minute the screen mirrors into two exact halves. After quitting Safari I then realise that has also done the same with the finder desktop etc. And no, it isn't the window splitting function. I have exactly the same system OS and Safari on my work iMac 27", 2017 and tried to reproduce the exact scenario but no glitch.
I am specifying Safari in particular because the glitch doesn't happen, with the exact scenario using Firefox or Chrome on the effected iMac. I have attached two videos to better show what I am facing. I have not, even after scouring the internet and here, found any posts regarding this strange glitch.
Thanks for any information in advance.
