How to catch a Viber request?

Question

API

Decided to track Viber mobile app requests through Fiddler and Xposed, but Fiddler doesn't show anything.
I think the point is that viber sends requests via tcp or udp protocol, which Fiddler does not see.
Public API is not an option, I need an app.
Is there a way to get the data it sends?

Answer 1

I only dealt with REST API for bots!
The desktop application sends requests to Viber servers and receives them.
The only thing I saw in the Header is that the Jetty (JAVA) library is used, according to user-agent /
But the request itself, its composition and syntax, we will not see in any way.