They don't say "JavaScript, HTML, and CSS" because it isn't just JavaScript, HTML, and CSS. It's any technology that can run in the browser, such as Yew or Mapl

They don't say "JavaScript, HTML, and CSS" because it isn't just JavaScript, HTML, and CSS. It's any technology that can run in the browser, such as Yew or Maple for example. Arguably those Rust-based frontend libraries are the main focus, even, over something like React. FLOSS also means a different thing from Open Source because of the "Libre" aspect. I don't see why being different is considered bad here, as its whole shtick is that it's an alternative.