For a less technical view please see https://test-cors.appspot.com/#friendly.

    This test suite makes requests to https://cors-test.appspot.com/, see that page for implementation details. The code is on github at https://github.com/rapportive-oss/cors-test

    CORS testing service provided by Rapportive, contact conrad@rapportive.com.

    For technical details, see https://test-cors.appspot.com/#technical.