And it doesn't give us any way of knowing that things have failed...
So we need to wait for a click to use the mediasource framework.
Some preparatory work in r22864. r22865 toggles the audio on and off using the speaker icon in the top bar.
To make this better, we could give some indication to the user that the server wants to send audio (we do have silence detection: #1617) using a "blinking" speaker icon or something. But this will do for now.
IE is not behaving, who would have guessed.
Moving "audio available" notification to #2325
Nothing more we can do (apart from #2325), so r23789 just avoids trying to start audio on connection with Firefox.
this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/2322