so, you are running a webrtc webapp in chrome on your android device, and then you start another app, which puts the chrome app into the background.
I'm guessing that the browser is freezing stuff because its in the background now.
You could check this hypothesis by playing a youtube video in chrome and then starting up messenger. If you see the same issue, then its just chromes behavior.
If you run your webapp inside your own app using a webview, you can probably get around this behavior.