From the maintainer Li Haoyi: I'm putting a 500USD bounty on this issue, payable by bank transfer on a merged PR implementing this.

Scala.js now supports WebAssembly output (https://www.scala-js.org/news/2024/09/28/announcing-scalajs-1.17.0/). We should have an example doc-test in example/scalalib/web/ exercising the hello-world Scala.js webassembly dev workflow using Mill and include it in scalalib/web-examples.adoc as documentation.