Jest: SyntaxError: Unexpected token 'export' happens at tslib.es6.js

Question

I get this error:

C:\Users\myname\Projects\ConfigEditor\MesConfiguration.WebClient\node_modules\tslib\tslib.es6.js:24
    export function __extends(d, b) {
    ^^^^^^

    SyntaxError: Unexpected token 'export'

My jest-esm.config.mjs looks like this

const jestConfig = {
  preset: 'jest-preset-angular/presets/defaults-esm',
  extensionsToTreatAsEsm: ['.ts'],
  globals: {
    'ts-jest': {
      useESM: true,
      stringifyContentPathRegex: '\\.(html|svg)$',
      tsconfig: '<rootDir>/tsconfig-esm.spec.json',
    },
  },
  testEnvironment: 'jsdom',
  moduleFileExtensions: ['ts', 'html', 'js', 'json', 'mjs'],
  resolver: 'jest-preset-angular/build/resolvers/ng-jest-resolver.js',
  transformIgnorePatterns: ['node_modules/(?!.*\\.mjs$)'],
  transform: {
    '^.+\\.(ts|js|mjs|html|svg)$': 'jest-preset-angular',
  },
  globalSetup: 'jest-preset-angular/global-setup',
  moduleNameMapper: {
    //tslib: 'tslib/tslib.mjs',
    tslib: 'tslib/tslib.es6.js',
    "@shared/(.*)": "<rootDir>/src/app/shared/$1",
    "@editors/(.*)": "<rootDir>/src/app/editors/$1",
    "@dashboard/(.*)": "<rootDir>/src/app/dashboard/$1",
    "@env": "<rootDir>/src/environments/environment",
  },
  setupFilesAfterEnv: ['<rootDir>/src/setup-jest.ts'],
}

export default jestConfig;

package.json has

"type": "module",

I start the test with

"test-esm": "node --experimental-vm-modules --no-warnings node_modules/jest/bin/jest.js -c=jest-esm.config.mjs --no-cache",

What ist wrong?

After renaming the tslib.es6.js to tslib.mjs the error is gone, but this is no solution. It should work after any yarn install