Improve GCC/ Minifier documentation

[OndrejSpanel]

I would like to experiment with the new minifier a bit. How can I control if the new minifier or GCC is used?

I find the documentation about scalaJSLinkerConfig a bit lacking, esp. when Google often shows me pages which are quite old.

The documentation I am aware of:

https://www.scala-js.org/doc/project/module.html https://www.scala-js.org/doc/internals/compile-opt-pipeline.html

scala-js/scala-js#4482 mentions:

We automatically enable the new minifier under fullLink when GCC is disabled. This can be overridden with a scalaJSLinkerConfig setting.

There is no more explanation.

In LinkerBackendImpl.scala I can see some functions which look they might do something:

withClosureCompilerIfAvailable withMinify

Similar properties can be seen in https://www.scala-js.org/api/scalajs-linker-interface-js/latest/org/scalajs/linker/interface/StandardConfig.html, but there is no documentation for them.

I guess when I want to use the new minifier I want:

fullOptJS / scalaJSLinkerConfig ~= (_.withClosureCompiler(false).withMinify(true))