How to check payload in browser?

[Quitalizner]

Websockets allow the payload in/out to be monitored in the network tab.
Geckos.io doesn't seem to do the same.

How do I check the incoming and outgoing payload?

[yandeu]

In chrome it's chrome://webrtc-internals/

[Quitalizner]

I can only see the stats, not the actual data received and sent.
Is there any way to see that?