I would like to use Webpack 4 to transpile on one side my ES6 Javascript separately from my Sass:
extract-text-webpack-plugin does not play well with webpack 4.
According to Michael Ciniawsky:
extract-text-webpack-plugin reached a point where maintaining it become too much of a burden and it’s not the first time upgrading a major webpack version was complicated and cumbersome due to issues with it
mini-css-extract-plugin is here to overcome those issues.
see here for more information about this topic