Oh, it seems to be working!
And I must now confess that apparently I said something very incorrect a few hours ago. Actually what had happened was, when selecting an infinite research, I had selected one of the military researches. After reading your comment about how it would only show the color(s) of the sciences that were being used, I started a different research which used all of them and saw that it was still only changing between grey and gold.
In fact, what I had done I realize now when I loaded the save is I had QUEUED another research which used all ten colors, but it was still working on an infinite military research which used only two colors of packs: grey and gold.
That's my bad! I assumed that this behavior was wrong because I thought I was researching with all the science packs and it looked more like it was brightening and dimming, because the grey science pack was very dark, nearly black.
The new setting worked perfectly to fix this, and then I looked at my research and realized the problem. Sorry for making you run in circles on that one! When I did my initial testing in my regular save I was researching with several sciences... but I was also having an issue with all of my Advanced Labs from Krastorio looking weird. Since I didn't go back to my regular save to test I didn't notice this.
In any case, everything seems to be working perfectly now, no need for you to reinstall your Steam Deck OS just to test.