Ruby Sass has reached end-of-life and should no longer be used.

[sander-bol]

Upon running bundle install, a post-install message is emitted:

Ruby Sass has reached end-of-life and should no longer be used.

• If you use Sass as a command-line tool, we recommend using Dart Sass, the new
  primary implementation: https://sass-lang.com/install
• If you use Sass as a plug-in for a Ruby web framework, we recommend using the
  sassc gem: https://github.com/sass/sassc-ruby#readme
• For more details, please refer to the Sass blog:
  https://sass-lang.com/blog/posts/7828841

[tombruijn]

Hey @sbol-coolblue, Thanks for the report!

This site doesn't use Sass, but it's part of the GitHub pages gem bundle by default. This warning can be ignored. There is an issue open for this upstream. Hopefully it will be resolved soon.

• github-pages jekyll-sass-converter dependency is still version 1.5.2 github/pages-gem#813

Alternatively, we could use the Jekyll gem directly, without the github-pages gem. That will require a lot less gems and works roughly the same.

[tombruijn]

This is fixed by using the Jekyll gem directly, without the github-pages gem, in commit ecccaeb.