Repository: yt-dlp
Issue: --extract-audio deletes already-downloaded videos
Labels: enhancement,PR-needed,core:post-processor

### DO NOT REMOVE OR SKIP THE ISSUE TEMPLATE

- [X] I understand that I will be **blocked** if I *intentionally* remove or skip any mandatory\* field

### Checklist

- [X] I'm reporting a bug unrelated to a specific site
- [X] I've verified that I'm running yt-dlp version **2023.03.04** ([update instructions](https://github.com/yt-dlp/yt-dlp#update)) or later (specify commit)
- [X] I've checked that all provided URLs are playable in a browser with the same IP and same login details
- [X] I've checked that all URLs and arguments with special characters are [properly quoted or escaped](https://github.com/yt-dlp/yt-dlp/wiki/FAQ#video-url-contains-an-ampersand--and-im-getting-some-strange-output-1-2839-or-v-is-not-recognized-as-an-internal-or-external-command)
- [X] I've searched [known issues](https://github.com/yt-dlp/yt-dlp/issues/3766) and the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues **including closed ones**. DO NOT post duplicates
- [X] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)

### Provide a description that is worded well enough to be understood

When using `-x` to get an audio-only version, already-downloaded videos are reused (great!) ... and immediately deleted  :sweat_smile: 

The easiest way to trigger this is to download a video with `yt-dlp` and immediately re-download it again with `-x`, as done in the verbose output below.

### Provide verbose output that clearly demonstrates the problem

- [X] Run **your** yt-dlp command with **-vU** flag added (`yt-dlp -vU <your command line>`)
- [ ] If using API, add `'verbose': True` to `YoutubeDL` params instead
- [X] Copy the WHOLE output (starting with `[debug] Command-line config`) and insert it below

### Complete Verbose Output

```shell
$ cd $(mktemp -d)  # Switch to a temporary, empty directory

$ yt-dlp 'https://www.youtube.com/watch?v=OWhV31hq8Xs'
[youtube] Extracting URL: https://www.youtube.com/watch?v=OWhV31hq8Xs
[youtube] OWhV31hq8Xs: Downloading webpage
[youtube] OWhV31hq8Xs: Downloading android player API JSON
[youtube] OWhV31hq8Xs: Downloading MPD manifest
[SponsorBlock] Fetching SponsorBlock segments
[SponsorBlock] No matching segments were found in the SponsorBlock database
[info] OWhV31hq8Xs: Downloading 1 format(s): 248-dash+251
[dashsegments] Total fragments: 70
[download] Destination: Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].f248-dash.webm
[download] 100% of   25.58MiB in 00:00:15 at 1.66MiB/s
[dashsegments] Total fragments: 1
[download] Destination: Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].f251.webm
[download] 100% of    6.24MiB in 00:00:00 at 12.33MiB/s
[Merger] Merging formats into "Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].webm"
Deleting original file Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].f248-dash.webm (pass -k to keep)
Deleting original file Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].f251.webm (pass -k to keep)
[Metadata] There isn't any metadata to add

$ ls -l  # Whole video is now present as a `.webm`
.rw-r--r-- 33M nicoo 29 juil.  2019 Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].webm

$ yt-dlp -vU -x 'https://www.youtube.com/watch?v=OWhV31hq8Xs'
[debug] Command-line config: ['-vU', '-x', 'https://www.youtube.com/watch?v=OWhV31hq8Xs']
[debug] User config "/home/nicoo/.config/yt-dlp/config": ['--socket-timeout', '10', '--sponsorblock-mark', 'all']
[debug] Encodings: locale UTF-8, fs utf-8, pref UTF-8, out utf-8, error utf-8, screen utf-8
[debug] yt-dlp version stable@2023.03.04 [392389b7d] (pip)
[debug] Python 3.10.10 (CPython x86_64 64bit) - Linux-6.1.15-x86_64-with-glibc2.35 (OpenSSL 3.0.8 7 Feb 2023, glibc 2.35)
[debug] exe versions: ffmpeg 4.4.3 (setts), ffprobe 4.4.3, rtmpdump 2.4
[debug] Optional libraries: Cryptodome-3.17, brotli-1.0.9, certifi-2022.12.07, mutagen-1.46.0, sqlite3-2.6.0, websockets-10.4
[debug] Proxy map: {}
[debug] Loaded 1786 extractors
[debug] Fetching release info: https://api.github.com/repos/yt-dlp/yt-dlp/releases/latest
Available version: stable@2023.03.04, Current version: stable@2023.03.04
yt-dlp is up to date (stable@2023.03.04)
[youtube] Extracting URL: https://www.youtube.com/watch?v=OWhV31hq8Xs
[youtube] OWhV31hq8Xs: Downloading webpage
[youtube] OWhV31hq8Xs: Downloading android player API JSON
[youtube] OWhV31hq8Xs: Downloading MPD manifest
[debug] Sort order given by extractor: quality, res, fps, hdr:12, source, vcodec:vp9.2, channels, acodec, lang, proto
[debug] Formats sorted by: hasvid, ie_pref, quality, res, fps, hdr:12(7), source, vcodec:vp9.2(10), channels, acodec, lang, proto, filesize, fs_approx, tbr, vbr, abr, asr, vext, aext, hasaud, id
[SponsorBlock] Fetching SponsorBlock segments
[debug] SponsorBlock query: https://sponsor.ajay.app/api/skipSegments/6f64?service=YouTube&categories=%5B%22selfpromo%22%2C+%22outro%22%2C+%22preview%22%2C+%22intro%22%2C+%22chapter%22%2C+%22sponsor%22%2C+%22filler%22%2C+%22poi_highlight%22%2C+%22music_offtopic%22%2C+%22interaction%22%5D&actionTypes=%5B%22skip%22%2C+%22poi%22%2C+%22chapter%22%5D
[SponsorBlock] No matching segments were found in the SponsorBlock database
[info] OWhV31hq8Xs: Downloading 1 format(s): 251
[debug] Invoking dashsegments downloader on "https://rr2---sn-uigxx50n-8pxr.googlevideo.com/videoplayback?expire=1678466874&ei=2goLZNX7B4WE6dsPn6K92Ao&ip=77.117.204.85&id=o-AHh3PP4atskTcW6YylLKsT2qWfT1bY0_1WnKlyA-6nVm&itag=251&source=youtube&requiressl=yes&mh=ak&mm=31%2C29&mn=sn-uigxx50n-8pxr%2Csn-h0jeened&ms=au%2Crdu&mv=m&mvi=2&pl=23&initcwndbps=1050000&spc=H3gIhrcaw8Z1GNl5QPaT_CNXftR339o&vprv=1&svpuc=1&mime=audio%2Fwebm&gir=yes&clen=6539180&dur=366.621&lmt=1564419022836406&mt=1678444872&fvip=1&keepalive=yes&fexp=24007246&c=ANDROID&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cspc%2Cvprv%2Csvpuc%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIgX80YX0bxIUlydhd4sqaW76ieCvmRfHbjx6A-z5asrIoCIQCOLCmLfKV_K4L-su-stRVLx5WqmzxCEDViqAJe15qDNg%3D%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRAIgRuUGBO9P2ZWE6vMMRYtEzmQk8EZwOSoV8cJF_xfNsyECIDqsnIjaqITmx237Zgk4K1Lz9o8JFFIrDGsUMEaPIFyB"
[download] Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].webm has already been downloaded
[download] 100% of   31.81MiB
[debug] ffmpeg command line: ffprobe -show_streams 'file:Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].webm'
[ExtractAudio] Destination: Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].opus
[debug] ffmpeg command line: ffmpeg -y -loglevel repeat+info -i 'file:Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].webm' -vn -acodec copy -movflags +faststart 'file:Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].opus'
Deleting original file Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].webm (pass -k to keep)
[Metadata] There isn't any metadata to add

$ ls -l  # Video file is indeed gone
.rw-r--r-- 6,5M nicoo 29 juil.  2019 Mission To Mars OST 2000 - A Martian [OWhV31hq8Xs].opus
```