1669507 - Camera/microphone privacy indicators in URL bar should stay on for 3 seconds minimum.

Status: NEW

(Core :: WebRTC: Audio/Video, defect, P3)

Description

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

From w3c/mediacapture-main#724 on the in-browser camera/microphone privacy indicators:

The spec says:
Any false-to-true transition indicated MUST remain observable for a sufficient time that a reasonably-observant user could become aware of it.

Current implementations seem to limit the observability of the transition if getUserMedia is called and the track got stopped shorter after that
The following fiddle https://jsfiddle.net/6axho8Lj/ shows the current behavior. The faster the camera start up time, the shorter the capture indicator.

Should we provide more guidelines about what is 'sufficient time'. Mention the case of call getUserMedia then stop the tracks?
3 seconds is already used in the spec: 'the UA SHOULD relinquish the device within 3 seconds'.
Is 3 seconds a good suggestion?

Firefox actually performs decently on desktop in the above fiddle, with the red camera indicator in the URL bar staying on for 2-3 s.

However, this looks like a delay from the page using the camera track in a sink, since in a straight obtain-and-stop https://jsfiddle.net/jib1/sadnvczh/ we perform much worse to where the URL indicator is barely noticeable. (click the Start! button every few seconds with ☑ Remember this decision checked).

To be clear, we're talking about the in-browser camera indicator in the URL bar. Thankfully, Firefox also turns on the hardware camera light which stays on for 3 seconds as it should. But not all cameras have lights or face the user, and microphones rarely have lights.