A method for delivering cross-site media, comprising: receiving, by a data processing system from a client device, a first request for media content at a first domain embedded in a content element from a second domain, the first request including a predefined identifier indicating that the client device is configured to restrict cross-domain redirection; determining, by the data processing system, responsive to identifying the first domain as different from the second domain and to identifying the predefined identifier indicating that the client device is configured to restrict cross-domain redirection, that the first request comprises a first content type header having a first predetermined value indicating a type of the requested media content; generating, by the data processing system, a first response comprising a redirect address of the requested media content element in a body of the first response and a status identifier indicating success in a header of the first response; receiving, by the data processing system from the client device, a second request including the redirect address of the requested media content element and a second content type header having a second predetermined value indicating that the client device is expecting the media content element; accessing, by the data processing system, responsive to determining that the second request comprises the content type header having the second predetermined value indicating that the client device is expecting the media content element, the media content element using the redirect address in the second request; generating, by the data processing system, a second response comprising the media content element in a body of the second response; and transmitting, by the data processing system, the second response to the client device. receiving, by a data processing system from a client device, a first request for media content at a first domain embedded in a content element from a second domain, the first request including a predefined identifier indicating that the client device is configured to restrict cross-domain redirection; determining, by the data processing system, responsive to identifying the first domain as different from the second domain and to identifying the predefined identifier indicating that the client device is configured to restrict cross-domain redirection, that the first request comprises a first content type header having a first predetermined value indicating a type of the requested media content; generating, by the data processing system, a first response comprising a redirect address of the requested media content element in a body of the first response and a status identifier indicating success in a header of the first response; receiving, by the data processing system from the client device, a second request including the redirect address of the requested media content element and a second content type header having a second predetermined value indicating that the client device is expecting the media content element; accessing, by the data processing system, responsive to determining that the second request comprises the content type header having the second predetermined value indicating that the client device is expecting the media content element, the media content element using the redirect address in the second request; generating, by the data processing system, a second response comprising the media content element in a body of the second response; and transmitting, by the data processing system, the second response to the client device.