Sass-loader error 'options has an unknown property 'indentedSyntax'' when upgrading Vuetify from 1.5 to 2

Question

I am upgrading Vuetify in my Vue CLI 3 project from version 1.5 to 2. I have followed these instructions, doing a full install. Since the upgrade, running \'npm run serve\'

Answer 1

Actually you are using sass-loader 8+ and it has an option a little bit different.
Try using prependData instead of data.
Check this github issue

module.exports = {
    css: {
      loaderOptions: {
        sass: {
          prependData: `@import "~@/sass/main.scss"`
        }
      }
    }
}