A graphical user interface (GUI) element rendering method. A GUI element rendering method can include serving a Web page to a Web browser. The Web page can include markup which defines a form and the form can include one or more submittable input elements, each submittable input element having a corresponding key-value pair. The key-value pair can include an identifying key and a value, and one or more of the identifying keys can include a shallow form submit key indicating a request for advanced GUI element processing. One or more of the submitted key-value pairs can be received from the Web browser from among which a shallow form submit key can be identified. In consequence, advanced GUI element processing can be performed based upon values which are associated with the identified shallow form submit key.