webpack.config.js

const {resolve} = require('path');

module.exports = [
    {
        mode: 'development',
        target: 'web',
        entry: './src/app/index.tsx',
        output: {
            path: resolve(__dirname, 'build'),
            filename: 'app.js',
        },
        resolve: {
            alias: {
                react: require.resolve('react'),
            },
            extensions: ['.tsx', '.ts', '.js', '.scss'],
        },
        module: {
            rules: [
                {
                    test: /\.[tj]sx?$/,
                    use: ['babel-loader'],
                    include: [
                        resolve(__dirname, 'src'),
                        require.resolve('@diplodoc/mermaid-extension'),
                    ],
                }, {
                    test: /\.s?css$/,
                    use: [
                        {
                            loader: 'style-loader',
                            options: {
                                insert: function insertBeforeAt(element) {
                                    /* eslint-env browser */
                                    const parent = document.querySelector('head');
                                    const target = document.querySelector('#custom-style');

                                    const lastInsertedElement =
                                        window._lastElementInsertedByStyleLoader;

                                    if (!lastInsertedElement) {
                                        parent.insertBefore(element, target);
                                    } else if (lastInsertedElement.nextSibling) {
                                        parent.insertBefore(
                                            element,
                                            lastInsertedElement.nextSibling,
                                        );
                                    } else {
                                        parent.appendChild(element);
                                    }

                                    window._lastElementInsertedByStyleLoader = element;
                                },
                            },
                        },
                        {loader: 'css-loader'},
                        {loader: 'sass-loader'},
                    ],
                }, {
                    test: /\.svg$/,
                    loader: 'react-svg-loader',
                },
            ],
        },
    },
];