In version 2.5 it was unreasonable.
In V2.9.1, even with Webbridge 3, the problem still exists. So far nobody could explain to me what exactly the problem with WebRTC is. The problem occurs with Chrome, Firefox and Safari. All browsers have the same error pattern. The error is in the product and not the browser.
I have an open case with Cisco about this problem.
I have sent him all information, I hope he will talk to a colleague from the development department.