Download audio-only as Webm / Keep Webm file "effectively" (without using -k)

[fx-pro]

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• You will be asked some questions and requested to provide some information, please read them carefully and answer honestly
• Put an x into all the boxes [ ] relevant to your issue (like this: [x])
• Use the Preview tab to see what your issue will actually look like

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Description of your issue, suggested solution and other information

Currently, to download the best quality audio from youtube video, we simply use
youtube-dl -x ULR

The application download the webm file, then quickly "get out" the opus file from webm container and immediately delete original webm file.

However, the opus file isn't widely supported, I want to keep the webm file.

Of course, the application suggest using "-k" to keep that file. But when we use -k, the whole video file (which is 8-10x bigger) would be downloaded.

Please add one more option for this purpose (download audio-only as Webm), or simply add webm to --audio-format

Thank you

[dstftw]

Don't use -x in the first place if you don't need any conversion.

[fx-pro]

@dstftw Could you please read my issue for one minute instead of close it immediately? Please.
We use -x to download the audio only instead of the big whole audio file.
The webm file is downloaded actually, but it was deleted.

Add "webm" to AUDIO-FORMAT is reasonable.

[fx-pro]

Anyway, I've changed the title of issues