1. A method comprising: receiving, by a server computer system, a first request originating from a first window of an application running on a client computer system, the first request including a resource identifier and a first window identifier corresponding to the first window; receiving, by the server computer system, a second request originating from a second window of the application running on the client computer system, the second request including the resource identifier and the first window identifier corresponding to the first window; sending, by the server computer system, a script that includes the resource identifier, the first window identifier, and a loopback identifier associated with the first request to the second window of the application; enabling the application running on the client computer system to execute the script to facilitate determination of whether the second window is a new window or an existing window, the determination comprising a comparison between the first window identifier included in the script and an actual window identifier of the second window; and enabling transmission of a third request, from the second window, to the server computer system that includes: the resource identifier, the first window identifier corresponding to the first window, and the loopback identifier when the first window identifier included in the script and the actual window identifier of the second window match; or the resource identifier, the actual window identifier of the second window, and the loopback identifier when the first window identifier included in the script and the actual window identifier of the second window do not match.