Electron: how to capture audio from only one app

Question

We are developing a desktop application using Electron with screenshare capability. For this we use the getUserMedia API. And we have the option to choose which screen or window to capture. This is part of the code for that

let constraints = {
    audio: {
        mandatory: {
            chromeMediaSource: 'desktop',
            chromeMediaSourceId: sourceId
        }                                   
    },
    video: {
        mandatory: {
            chromeMediaSource: 'desktop',
            chromeMediaSourceId: sourceId
        }                                   
    }
}
let stream = await navigator.mediaDevices.getUserMedia(constraints)

And we would like to only capture audio from the application that is being streamed. Is it possible to do this? Maybe some third party solutions?