How to see the amount of data transfer during pixel streaming?

Hi guys. I’m trying to see how much data is transfered during a pixel streaming session on the browser, but I cannot see the measurement anywhere. Take a look at this demo for example, after the page is loaded, I see no more request/response or data transfer when I interact with the scene.

What I’m understanding is that Pixel Streaming is something like a socket connection, where every interaction of the user is sent to the server, the server modifies the scene based on that interaction and sends back the result? Is my understanding correct? If it is there should be constant data transfer between the browser and the pixel streaming server, but why do I see nothing here?