Can I add custom functions to openxr?

I want to add the conference function to openxr. Do openxr have any extension interfaces that can be used? Then I can implement the conference function through the interface

OpenXR tends to be a lower-level interface: conferencing (shared experiences?) is a higher level capability that might be built on OpenXR but isn’t necessarily at the runtime level. That said, please see https://www.khronos.org/registry/OpenXR/#extprocess for details on how to propose an extension. In order to implement one, you’ll either need to have your own runtime, or implement your extension as an API layer.