charlie: I've noticed that this question, along with some of the others allows me to retry as many times as I want - it's like it never registers as completed. I made a short video to show you what I mean: https://youtu.be/BUOKXwMnu3I. To reproduce, I complete the question, click next (or reset or the previous question) and am then able to coplete it again.
I have done this puzzle but it is still blue, no matter how many times i do that.