If your Windows Start, taskbar, action center option is grayed out in Settings
Strange things are not always absent even now that Windows seems to be more stable and reliable than ever!
After Windows Features update I had of course to re-activate Desktop Gadgets using the Gadgetarian, and also reconfigure my colors. The second task proved more difficult, since the relevant option (Start, taskbar, and action center) in the “Colors” section of the Windows Settings was grayed out!
Here is how you can solve this problem. Just below the “Colors” section in the large menu column at the left you can see the “Themes” section. Go there, scroll a little and go to “Change theme”. Select and activate any theme you like. Now return to the “Colors” section.
Take care: Do not change there anything other at all except for the accent color (you can choose any color you like) and the “Show accent color on the following surfaces” option, which includes the now available! “Start, taskbar, and action center” option.