Legacy: This topic discusses extending operation views created using the Windows version Operations Dashboard for ArcGIS. This version of the application has been moved to Mature Support status. To learn more about the latest web-based version, see Operations Dashboard for ArcGIS.
Once an extension has been deployed to a web server and registered as an Operations Dashboard extension item in your ArcGIS organization, the contents of the manifest file are saved in the extension item. This means that any change made to your manifest file that is hosted on a web server will not be recognized by the registered extension. It is recommended to create a new extension rather than updating the manifest file, unless your extension is backwards compatible.
To learn more, see Deploy an extension.