
So, next, since I actually have 3 Macs (1 MacBook Pro 16 (2019 edition) running Catalina, 1 MacBook Pro (2012 edition) running Mojave and an iMac (2015 edition) running Mojave) I decided to try my Mojave iMac. And voila, no streaking problems at all and I didn't do anything special, i.e. cfg file etc.
iMac Mojave has the following specs:
I'll try the same thing on my Mojave MacBook Pro (2012 edition) tonight. So, it begs the question whether it is a Catalina problem or a 5500 GPU problem.
cytan