config-overrides.js

/* config-overrides.js */

module.exports = {
  // Extend/override the dev server configuration used by CRA
  // See: https://github.com/timarney/react-app-rewired#extended-configuration-options
  devServer: function(configFunction) {
    return function(proxy, allowedHost) {
      // Create the default config by calling configFunction with the proxy/allowedHost parameters
      // Default config: https://github.com/facebook/create-react-app/blob/master/packages/react-scripts/config/webpackDevServer.config.js
      const config = configFunction(proxy, allowedHost);

      // Set loose allow origin header to prevent CORS issues
      config.headers = {
        'Cross-Origin-Embedder-Policy': 'require-corp',
        'Cross-Origin-Opener-Policy': 'same-origin',
      }

      return config;
    };
  },
};