1. A method in a server for improving the loading of web resources, the method comprising: receiving a first request from a client network application for a Hypertext Markup Language (HTML) document, wherein the first request identifies a domain that hosts the HTML document; retrieving the requested HTML document, wherein the retrieved HTML document includes a plurality of client-side script objects; modifying the retrieved HTML document including inserting a client-side script loader or a reference to the client-side script loader into the retrieved HTML document, wherein the client-side script loader is configured to, when executed by the client network application, perform the following: initiate a single Transmission Control Protocol (TCP) connection with the server, and transmit a single second request to the server over the single TCP connection for the plurality of client-side script objects; and transmitting the modified HTML document to the client network application.