Pull audio only from a specific application (Pulseaudio)

[NBBZ]

I want the visualizer to take input only from a specific app.
for example: when I'm in a discord call and listening to spotify at the same time the visualizer picks up dicord and spotify at the same time as it should but I would like it to pick up only spotify, does it have such functionality?
(I'm on pulseaudio)

[dpayne]

I think this is possible but it'd probably involve some custom puslse audio logic. Right now it's not supported.