Why does Chrome not show the prompt with Allow or Disallow permission to microphone and webcam?

Question

I have built simple video chat with SimpleWebRTC, and when I start WebRTC on the Ubuntu Chrome 34 shows me the prompt with Allow or Disallow permission to microphone and webcam. I click allow and can start conversation if even I don't have webcam.

But when I start WebRTC on Windows 7 Chrome 33 doesn't show any prompt. But I can see cross webcam icon in address line. And when I try to allow Chrome to use microphone and webcam It's reloading. So what I need to do for showing the prompt as in Linux?

My code is:

    webrtc = new SimpleWebRTC({
        // the id/element dom element that will hold "our" video
        localVideoEl: 'publishers',
        // the id/element dom element that will hold remote videos
        remoteVideosEl: 'subscribers',
        // immediately ask for camera access
        autoRequestMedia: true
    });
    webrtc.on('readyToCall', function () {
        webrtc.joinRoom(sessionId);
    });

Also I can reproduce it with this demo. I got next error message in that demo app:

Failed to get access to local media. Error name was PermissionDeniedError. Continuing without sending a stream.

Answer 1

There's a new security feature on Chrome 59:

Temporarily stop permission requests after 3 dismissals Security

Temporarily stop an origin from requesting a permission following the third dismissal of a permission prompt. The stop will be lifted after some amount of time has passed (initially 1 week), after which the origin may request the permission again. A further dismissal will apply the temporary stop again.

For web developers who are testing features, the block can also be removed by changing the permission's setting in the lock icon's page info dialog, or by clearing your browsing data.

Source: https://www.chromestatus.com/features/6443143280984064