This project demonstrates that the Scratch pen color value 0 and 100 produce the same hue (pure red, #FF0000 in hexadecimal), and that the color values do not repeat themselves at multiples of 100, but multiples of 101. Each colored dot in the graph has the color value equal to its column number plus its row number. For example, the top left dot has the color value 0, and the bottom left dot has the value 9. In the second column, the top dot has value 100, and the bottom dot has the color value 109. The dots with white rings are the ones that have a pure red hue. You can use the color picker tool in your browser's developer tools to confirm this. I'm not sure what to make of this. Is there a thought behind this or did the developers just miss this? It is certainly not very intuitive.
Inspired by this comment by @gregatku: https://scratch.mit.edu/studios/25643089/comments/#comments-110088978
