Detecting user-actionable camera issues (e.g., camera shutters)

[guidou]

Devices sometimes allow users to disable a camera via various means (e.g, physical camera shutters, ). In many cases users want to use the camera but have forgotten that they have disabled it by using a shutter, for example. This is often detectable at the system level via some APIs, but on the Web it is not visible except as black frames or perhaps as a muted track. Since tracks can be muted for any reason, an application cannot reliably provide feedback to the user with an explanation and possible ways to fix the problem. Black frames may also be produced by other non-system-level reasons.

It would be good to address this use case on the Web platform. A possible way would be to add an optional field to the mute event with a reason for the mute. Another possibility is to change the muted property from bool to an enum, or add a new property or event to avoid breaking compatibility.