1129274 - Allow the getUserMedia camera light to go out when the camera is disabled

Status: RESOLVED WORKSFORME

(Firefox :: Site Permissions, defect)

Description

[Maire Reavy [:mreavy]]

Applications would like the camera light to go out when the user "mutes" from within the application via track.enabled=false.  Right now we don't allow that to avoid a malicious app faking release of the camera and capturing snapshots later.  This problem can be avoided by popping a request to re-authorize on re-enable (if persistent permissions haven't been granted).  

This is of most use to trusted applications with persistent permissions.

Comment 1

[Florian Quèze [:florian]]

(In reply to Maire Reavy [:mreavy] (Plz needinfo me) from comment #0)
> Applications would like the camera light to go out when the user "mutes"
> from within the application via track.enabled=false.  Right now we don't
> allow that to avoid a malicious app faking release of the camera and
> capturing snapshots later.  This problem can be avoided by popping a request
> to re-authorize on re-enable (if persistent permissions haven't been
> granted).  
> 
> This is of most use to trusted applications with persistent permissions.

I understand that this is needed for cases like Hello. But I think having to re-authorize in another chrome-prompt makes the "unmute" button in regular web page useless.

Here a suggestions to mitigate the privacy concern without degrading the UX too much:
- ensure that when the camera is enabled, the light says on for at least a few seconds (eg. 5s) to avoid malicious apps taking snapshots without the user noticing the camera light. (We would still turn off the light immediately when the video stream is permanently stopped; I'm just talking here about the case where the track is disabled/re-enabled).
- prompt the user to re-authorize only if the track has been disabled for some time (eg. a minute or two). This should avoid making the video mute button useless in cases I've commonly seen (eg. I mute the video if someone is coming next to me and asking me something, or if I'm about to sneeze in front of the camera during a call).

Comment 2

[Emma Zühlcke [:emz]]

I've tested this on https://meet.jit.si/. If I disable my camera on the website the camera sharing indicator in the identity section disappears. Enabling the camera again works without re-authorization.