MacBook Pro M1 external screen flickering

[Spectre8079]

I confirm StillColor's "Disable Dithering" fixed the flickering of my external monitors. And it's by far the only solution that worked for me!

Any downsides with that?

A little update of my experience with StillColor. Out of sheer boredom, I dug out my old problematic, flicker-monster (Asus VP28U) out of storage and installed the latest version of StillColor (V1.1), just to see if it would help. And it did – but only up to a certain point. I tested it for a few hours and while it did seem to eliminate the migraine inducing Eurotechno-like strobing for about 2 to 3 hours (plenty of time for the flickering to start), it did eventually creep back, ironically while on this very page (with MacOS Dark Mode turned on). However, the flashing was not as intense as it was previously. Toggling the 'Disable Dithering' option in the app's settings seems to stop & start the flickering, proof that the app does help but unfortunately did not get rid of it completely. This was on a 2020 Mac mini running Sequoia 15.1. No problems with the app so far.