config-overrides.js

const {
  override,
  getBabelLoader, 
  addWebpackModuleRule
} = require('customize-cra');

module.exports = (config, env) => {
  const babelLoader = getBabelLoader(config);
  
  return override(
    addWebpackModuleRule(
      test: /\.worker\.ts$/,
      use: [
        {
          loader: 'worker-loader',
        },
        {
          loader: babelLoader.loader,
          options: {
             babelLoader.options
          }
        }
      ]
    )
  )(config, env)
}