How to fix Sass Loader Error: Invalid options object that does not match the API schema with JavaScript?

To fix Sass Loader Error: Invalid options object that does not match the API schema with JavaScript, we make sure the Webpack config has properties in the right places.

For instance, we write

module.exports = {
  loader: "sass-loader",
  options: {
    sassOptions: {
      indentedSyntax: true,
    },
  },
};

in webpack.config.js, to add the indentedSyntax property into sassOptions.