Comment 4 for bug 1535818

this isn't working in OTA11, you can't switch cameras using in-page web controls, you can go to the privacy settings in the browser preferences and set the default camera to front and reload the page, but you seem to have to do that every time you start the browser.
tried using talky.io and the samples page https://webrtc.github.io/samples/src/content/devices/input-output/