Does media session work with WebAudio?

[mmontag]

Explainer says:

A music website can tell the user agent that it wants to receive "previous/next track" commands, so that it can switch tracks when these commands are received.

Sounds great!

README says:

Access to media keys and lock screen UI will only be granted when audio playback begins, ensuring that audio focus is not taken from another application prematurely and that lock screen UI is only shown when it can be used.

Oh...so what determines "when audio playback begins"?

In Chrome 73 it seems that an <audio> or <video> element needs to be streaming audio and the WebAudio/AudioContext use case requires hacks.

1. Is Chrome doing this right? I filed an issue https://bugs.chromium.org/p/chromium/issues/detail?id=944538
2. Can we update the README and Explainer based on the outcome of these discussions: Collect media keys use cases mediasession#1 Figure out the coupling between audio focus/session, audio playback and remote control events mediasession#9 Making this work with Flash mediasession#14 Simplify MediaSession somewhat to not require audio playback mediasession#17 Integrate with Web Audio mediasession#48

[voxpelli]

Seems like any mention of WebAudio/AudioContext/"audio-producing objects" that was introduced in w3c/mediasession#48 was removed in w3c/mediasession#135 in an effort to "Updating the spec to match current explainer" – without any easily discoverable explanation on why

[mounirlamouri]

To handle Web Audio, we need to go through the Audio Focus API as Web Audio doesn't take audio focus by default on all browsers and changing would have significant side effects.

[rektide]

w3c/mediasession#277 indicates Audio Focus API is not active or being pursued. Is there something more in-reach that can be done to make WebAudio capable of working with MediaSessions?

[eric-carlson]

The Media WG is reviving the Audio Focus API, retitled the Audio Session API

[youennf]

Right, I would think that if WebAudio is used with an audioSession type equal to "playback", starting web audio should make the media session becoming active.
Moving this issue to audio session API.