Could you at least explain those configrations?

[CaptainJon]

As what it means in the title

I looked at the source code here for this extension. It uses js-beautify and applies the beautify.options to it. Agree, the options as shown in readme here don't work even after adapting to settings.json syntax.

A search for js-beautify in https://code.visualstudio.com/docs indicates that js-beautify is the standard built-in beautifier for CSS for vscode. https://code.visualstudio.com/Docs/languages/CSS#_formatting

I'm looking into a way to use additional options with the beautifier:
https://github.com/beautify-web/js-beautify