Feature request: Make "Audio Only" offer conversion to audio-only containers/formats

[rmader]

Thanks a lot for the app, I like it a lot and the UI is just gorgeous!

I'd like to suggest / request one improvement for the "Audio Only" download section: right now it seems to only offer a video container with the video stream stipped:

ytDownloader, a similar app that I've been using before, offers a neat feature to extract the audio into a audio-only containers such as mp3:

I'd love to see that in Varia as well. If you don't want to work on that yourself but would consider accepting a corresponding contribution, that'd also be great to know as I'd consider having a look :)

[giantpinkrobots]

We do have FFmpeg at our command here. There could be a banner on the top or bottom of the download dialog for example, to convert it to another format afterwards.