The current site has issues with colourblind support, for multiple forms of colourblindness.
For example, dark-orange on orange is used in the top-right of the homepage, which appears to be almost invisible to red-green and blue-yellow. To check a page, I have been using this colourblind tester. The three options I have been using are Protan, Deutan and Tritan.
If any colourblind users want to contribute their eyes, they could help flag particularly troublesome pages for review.