I use XD every day, and I was extremely surprised to see the color picker looking like in the video I attached. It's a lot darker, it looks totally different than before and it's pretty much useless. Is this a bug? It's totally unusable.
This is a known issue with the latest version and has also been discussed in this thread.
All we can do for now is wait for a fix 🙂
Technically, the selected color is correct (the color that should be at the x & y coordinates of the selector), it's just that the picker area itself has something like a dark gradient on it.