When UserMedia was first introduced to us mortals, there was no way to support proper audio capture other than mic but today there IS, as C3 shows.
I know it's kinda awkward to ask today, understanding that C2 is retired and doing that may be a huge work but could anyone make a behavior for UserMedia or make a totally new video+sound recorder plugin please?
And another smaller thing - a separate in-game audio recorder.
EDIT: probably hugely unrealistic but an option to exclude some layers from video capture would be cherry on a pie.