The present approach relates to facilitating the diagnosis of one or more performance issues associated with running an application (and widgets in the application) on a client instance hosted by one or more data centers by allowing script comparison, configuration comparison, and so forth, all in one interface, without the need for a user to navigate between various windows and/or interfaces. In accordance with the present approach, one or more performance issues are determined based on a first set of data indicative of an initial version of the application and a second set of data indicative of a customized version of the application. After determining the one or more performance issues, a visualization of diagnosis data associated with one or more widgets may be generated in response to executing the customized application to categorize the one or more widgets based on a severity of the one or more performance issues.