Upgrade also babel, deck.gl, node-sass, sass-loader, node-sass. Sort package.json.
const { merge } = require('webpack-merge') const common = require('./webpack.client.common.js') module.exports = merge(common, { mode: 'development', devtool: 'source-map', devServer: { hot: true, port: 8080, open: true, historyApiFallback: true, publicPath: '/' } })