13. The computer program product of claim 11 , wherein the program code is further executable by at least one processor to: download, by the application, the default widget renderer for rendering the second widget type from a network location specified by the document.
13. The computer program product of claim 11 , wherein the program code is further executable by at least one processor to: download, by the application, the default widget renderer for rendering the second widget type from a network location specified by the document. 14. The computer program product of claim 13 , wherein: the application comprises a web browser; and the default widget renderer comprises JavaScript code that is processed by the web browser.