Ubiquitous client side customization of Web applications

JavaScript has empowered users of Web applications. Using tools like Greasemonkey they can customize the application according to their specific needs through the injection of user scripts. The implementation approach, however, usually involves either extensions in the browser or client side proxies which go against the very nature of a Web application. The reason is that the customized application is not available in an ubiquitous manner anymore since the user needs to install and configure a piece of software in every place where he plans to use the application. We propose a software architecture that uses existing standards to store and fetch the needed information to support client side customization in a way that the modified application is still available from any browser and any computer as it was the original one. This paper describes the proposed architecture and a prototype implementation as a proof of concept. A variety of user scripts were successfully tested on the prototype. Once properly configured, the customized application was accessed from different machines using different standard versions of the browsers. The customized application remains thus universally accessible and we do not need to loose this crucial advantage.