logixoul Ok, I tested it. Here are my results:
npx mira settings --dither-mode 0
This is the default. It flickers (when moving mouse on a gray field)
npx mira settings --dither-mode 1
no flicker, because everything is black&white (binary!)
npx mira settings --dither-mode 2
no flicker, because only spatial dithering is used!
npx mira settings --dither-mode 3
no flicker; very slow refresh rate (1Hz)
I'll use mode 2 for now. Will see if it relieves my eyestrain.