Uncaught ReferenceError: Cesium is not defined

Followed Set up webpack config 1 step by step, but when starting the server, get a webpack error saying that “Cesium” isn’t defined.

However, my app runs cesium/resium perfectly fine

Here is my webpack.config.js:

const HtmlWebpackIncludeAssetsPlugin = require("html-webpack-include-assets-plugin");
const CopyWebpackPlugin = require("copy-webpack-plugin");
const Webpack = require("webpack");
module.exports = {
    entry: './src/index.js',
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader',
                },
            },
            {
                test: /\.html$/,
                use: {
                    loader: 'html-loader',
                },
            },
            {
                test: /\.css$/,
                use: [{ loader: 'style-loader' }, { loader: 'css-loader' }],
            },
            {
                test: /\.(png|jpg|gif|ico)$/,
                use: [
                    {
                        loader: 'file-loader',
                        options: {},
                    },
                ],
            },
        ],
    },
    externals: {
        cesium: "Cesium",
    },
    output: {
        path: __dirname + '/src/',
        filename: 'index.min.js',
    },
    plugins: [
        new Webpack.DefinePlugin({
            CESIUM_BASE_URL: JSON.stringify("cesium"),
        }),
        new CopyWebpackPlugin([
            {
                from: "node_modules/cesium/Build/Cesium",
                to: "cesium",
            },
        ]),
        new HtmlWebpackPlugin({
            template: './src/index.html',
            filename: './index.html',
            favicon: './src/img/favicon.ico',
        }),
        new HtmlWebpackIncludeAssetsPlugin({
            append: false,
            assets: ["cesium/Widgets/widgets.css", "cesium/Cesium.js"],
        }),
    ],
};

Ideally, I’d like to figure out what is causing the error and resolve it, even though the app runs resium/cesium fine.

[GRTO]

any updates on this? I got the same error as @garretth95 and Cesium and Resium were installed.

[garretth95]

Neither of those suggestions work for me. Adding scripts to HtmlWebpackPlugin, nor adding the script tag in index.html. Tried adding this to index.html: <script src="../node_modules/cesium/Build/CesiumUnminified/Cesium.js"></script>

Still confused what the issue is here.