CONSOLE ERROR: Access to resource at 'http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=1' from origin 'http://127.0.0.1:8000' has been blocked by CORS policy: The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'. CONSOLE ERROR: Access to resource at 'http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=2' from origin 'http://127.0.0.1:8000' has been blocked by CORS policy: The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'. CONSOLE ERROR: Access to resource at 'http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=3' from origin 'http://127.0.0.1:8000' has been blocked by CORS policy: The value of the 'Access-Control-Allow-Credentials' header in the response is '' which must be 'true' when the request's credentials mode is 'include'. Test that EventSource cross-origin requests with credentials fail until the correct CORS headers are sent. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS es = new EventSource("http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=1", {'withCredentials': true}) did not throw exception. PASS es.withCredentials is true PASS count != 4 && count != 5 is true PASS es = new EventSource("http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=2", {'withCredentials': true}) did not throw exception. PASS es.withCredentials is true PASS count != 4 && count != 5 is true PASS es = new EventSource("http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=3", {'withCredentials': true}) did not throw exception. PASS es.withCredentials is true PASS count != 4 && count != 5 is true PASS es = new EventSource("http://127.0.0.1:8080/eventsource/resources/es-cors-credentials.php?count=4", {'withCredentials': true}) did not throw exception. PASS es.withCredentials is true PASS evt.origin.indexOf('http://127.0.0.1:8080') === 0 is true PASS evt.data is "DATA1" PASS evt.lastEventId is "77" PASS count is 5 PASS evt.origin.indexOf('http://127.0.0.1:8080') === 0 is true PASS count is 5 PASS evt.data is "DATA2" PASS successfullyParsed is true TEST COMPLETE