Not even 1. You can't select by RGB value something too light (or too dark) for the accent color if Windows think it would be illegible. It's even worse if you

Not even 1. You can't select by RGB value something too light (or too dark) for the accent color if Windows think it would be illegible. It's even worse if you have enabled transparency. I wish there was an override, because if I want pure white #FFFFFF as my accent color, that's my problem. I don't want to settle on a light grey.