Chrome may suspend the Web Audio context absent a user gesture

[samme]

An AudioContext must be created or resumed after the document received a user gesture to enable audio playback.

I get this warning in Chrome Canary (M65) on, eg, http://phaser.io/examples/v2/audio/fade-in (iframe), and on my localhost (no iframe) when I open a game tab in the background and then focus it. But I don't get it when doing the same on https://samme.github.io/phaser-examples-mirror/audio/fade%20in.html. Not sure why.

The audio context is created but with a suspended state. Playback appears to go normally but there's no audio output.

A workaround would be

if (game.sound.usingWebAudio &&
    game.sound.context.state === 'suspended')
{
  game.input.onTap.addOnce(game.sound.context.resume, game.sound.context);
}

[samme]

The AudioContext was not allowed to start. It must be [resumed] (or created) after a user gesture on the page. https://goo.gl/7K7WLu

https://samme.github.io/phaser-examples-mirror/audio/fade%20in.html

[samme]

Phaser can try to resume the audio context via mouseout, which is wrong and will fail.