I have a 2017 Macbook Pro 13 without touchbar. Its totally fine for me running Mac OS X 10.15.7. I do notice that I get eye strain with almost all recent web browsers, even though the rest of the system doesn't bother me. I am fine with Safari 13 that shipped with 10.15.7. This MBP has an Intel Core i5 Kaby Lake processor with Intel Iris Plus 640 graphics.
I suspected that dithering is somehow being enabled by these newer browsers when rendering web content - even though its apparently not enabled at a system level in this version of Mac OS X. So to test this I installed Windows 11 using bootcamp. After installing Windows and running all updates, I confirmed the UI was not causing eye strain. I then installed the current version of Firefox and Edge. Both browsers caused the same eye strain as they do on Mac OS X. I then loaded ditherig 2.1 and then restarted the browsers. Firefox doesn't seem bother me nearly as much with ditherig running. Edge seems a little better also, but it didn't bother me as much as Firefox. Chrome still bothers me. Previously I could only use versions of Firefox before the recent UI change (<89). I couldn't use any recent Chromium or webkit browsers on this system.
Can anyone explain this? Can temporal dithering be enabled on a per application basis? Is there some change that was adopted in all of the major web rendering engines over the past couple years that causes this? Can it be disabled using a setting or maybe custom CSS?