I know, who uses XMPP in 2016?
But turns out behind the scenes a number of people do... (In my case a mobile app that enables inter-device communication.)
I used a modified version of XMPPPeek which got me partway but seemed in my case to leave the client hanging waiting for a response after authentication. Not sure why.
This (see "Phase 3") was some helpful documentation for getting XMPPPeek working but in my case I was trying to use the existing mitmproxy CA root cert which got a bit complicated: https://www.beneaththewaves.net/Projects/Multipurpose_Man-in-the-Middle_VM.html#ExampleZAPandXMPPPeek
Tab closing link dump:
Oh, somewhere along the way I got a "EOF occurred in violation of protocol" error too, I think with XMPPPeek.