Chrome Postman与jQuery

I'm testing a WebSEAL secured RESTful service against Chrome Postman which works 100%. I pass in basic authentication credentials as required and send the request.

There is no authorization prompt in the browser, and the response returns the expected results without error.

However, when I try to do this in jQuery and run it via a browser, I get nowhere, exception CORS errors and other authorization 401 errors that I am not expecting.

In my opinion, Postman generates exactly the same XMLHttpRequest string that I would via any AJAX framework in JavaScript, yet Postman succeeds and normal JavaScript does not.

What is the difference here? I am completely at a lost.

// jQuery
var authorization = basic_auth('username', 'password1'),
    url = 'https://url.domain.name/service.svc';


$.ajax({
    url: url,
    method: 'GET',
    xhrFields: {
        withCredentials: true
    },
    beforeSend: function (req) {
        req.setRequestHeader('Authorization', authorization);
        req.setRequestHeader('Content-Type', 'application/json');                
    },
    success: function (s) {

    }
});

// XMLHttpRequest
var xml = new XMLHttpRequest(),
    authorization = basic_auth('username', 'password1'),
    url = 'https://url.domain.name/service.svc';
xml.open('GET', url, true);
xml.setRequestHeader('Authorization', authorization);
xml.setRequestHeader('Content-Type', 'application/json');
xml.setRequestHeader('Content-Length', 1000);
xml.onreadystatechange = function () {
    xhrResult(httpRequest);
};        
xml.send(null);

UPDATE & RESOLUTION

Chrome, by default, does not allow XS-XHR from localhost.