@orbite Well, color vision is a complex process, and we rarely see what's really presented by the technique. Actually you are not alone with your colorful perception of that background being a somewhat colorful grey. I also totally see it, that's why I was that surprised when your toot showed up in notifications again, and I realized the raw technical truth behind your background's grey.
Actually it's nice how a pretty picture can turn even the greyest grey into something pretty.