yt-dlp: [YouTube] nsig extraction now fails

Checklist

• I’m reporting a broken site
• I’ve verified that I’m running yt-dlp version 2022.01.21. (update instructions)
• I’ve checked that all provided URLs are alive and playable in a browser
• I’ve checked that all URLs and arguments with special characters are properly quoted or escaped
• I’ve searched the bugtracker for similar issues including closed ones. DO NOT post duplicates
• I’ve read the guidelines for opening an issue
• I’ve read about sharing account credentials and I’m willing to share it if required

Region

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Description

Starting sometime today (as of posting this), yt-dlp now throws an error about nsig extraction failing when downloading YouTube videos. I don’t know what caused this as earlier today no error would come up when downloading videos (perhaps Google changed something on their end). I don’t use an account for downloading videos either. I canceled the download shortly after the error comes up as it would take too long to actually download the video (my phone ISP throttles YouTube to 300KB/s). If you want me to attempt to download the video completely to see if something else happens please let me know.

Verbose log

[debug] Command-line config: ['-vU', 'https://www.youtube.com/watch?v=fCucjL2SmLE']                                   [debug] User config "/data/data/com.termux/files/home/.config/yt-dlp/config": ['--no-mtime', '--ignore-errors', '--min-sleep-interval', '4', '--max-sleep-interval', '20', '-o', '/data/data/com.termux/files/home/storage/shared/Youtube/%(playlist_index)s-%(title)s-%(id)s.%(ext)s', '-f', 'bv*+ba/b', '--remux-video', 'mp4/mkv']                             [debug] Encodings: locale UTF-8, fs utf-8, out utf-8, err utf-8, pref UTF-8
[debug] yt-dlp version 2022.01.21 [f20d607b0]              [debug] Python version 3.10.1 (CPython 64bit) - Linux-4.14.243-gb26579d061ac-aarch64-with-libc
[debug] exe versions: ffmpeg 4.4.1 (setts), ffprobe 4.4.1
[debug] Optional libraries: Cryptodome, mutagen, sqlite, websockets
[debug] Proxy map: {}
Latest version: 2022.01.21, Current version: 2022.01.21    yt-dlp is up to date (2022.01.21)
[debug] [youtube] Extracting URL: https://www.youtube.com/watch?v=fCucjL2SmLE
[youtube] fCucjL2SmLE: Downloading webpage
[youtube] fCucjL2SmLE: Downloading android player API JSON
[youtube] fCucjL2SmLE: Downloading player e06dea74
WARNING: [youtube] nsig extraction failed: You may experience throttling for some formats
n = SrIafPCsV8qC_dqlxb ; player = https://www.youtube.com/s/player/e06dea74/player_ias.vflset/en_US/base.js
fCucjL2SmLE: Traceback (most recent call last):
  File "/data/data/com.termux/files/usr/lib/python3.10/site-packages/yt_dlp/extractor/youtube.py", line 2412, in _decrypt_nsig
    self._player_cache[player_id] = self._extract_n_function(video_id, player_url)
  File "/data/data/com.termux/files/usr/lib/python3.10/site-packages/yt_dlp/extractor/youtube.py", line 2433, in _extract_n_function
    funcname = self._extract_n_function_name(jscode)
  File "/data/data/com.termux/files/usr/lib/python3.10/site-packages/yt_dlp/extractor/youtube.py", line 2421, in _extract_n_function_name
    return self._search_regex(
  File "/data/data/com.termux/files/usr/lib/python3.10/site-packages/yt_dlp/extractor/common.py", line 1186, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
yt_dlp.utils.RegexNotFoundError: Unable to extract Initial JS player n function name; please report this issue on  https://github.com/yt-dlp/yt-dlp . Make sure you are using the latest version; see  https://github.com/yt-dlp/yt-dlp  on how to update. Be sure to call yt-dlp with the --verbose flag and include its complete output.
 (caused by RegexNotFoundError('Unable to extract \x1b[0;94mInitial JS player n function name\x1b[0m; please report this issue on  https://github.com/yt-dlp/yt-dlp . Make sure you are using the latest version; see  https://github.com/yt-dlp/yt-dlp  on how to update. Be sure to call yt-dlp with the --verbose flag and include its complete output.')); please report this issue on  https://github.com/yt-dlp/yt-dlp . Make sure you are using the latest version; see  https://github.com/yt-dlp/yt-dlp  on how to update. Be sure to call yt-dlp with the --verbose flag and include its complete output.
[debug] Sort order given by extractor: quality, res, fps, hdr:12, source, codec:vp9.2, lang, proto
[debug] Formats sorted by: hasvid, ie_pref, quality, res, fps, hdr:12(7), source, vcodec:vp9.2(10), acodec, lang, proto, filesize, fs_approx, tbr, vbr, abr, asr, vext, aext, hasaud, id
[info] fCucjL2SmLE: Downloading 1 format(s): 303+251
[debug] Invoking downloader on "https://rr3---sn-uhvcpax0n5-jaxe.googlevideo.com/videoplayback?expire=1643708580&ei=Q6z4YZLtO9qG_9EP1qGQqAY&ip=2607%3Afb90%3Ab44a%3A86d0%3A2712%3Aece0%3A81de%3Afccc&id=o-ALYlukkQbrVn0GLFpxySaVPS-7J6aAvt2WWkXvhEMJW9&itag=303&source=youtube&requiressl=yes&mh=gV&mm=31%2C29&mn=sn-uhvcpax0n5-jaxe%2Csn-vgqsknee&ms=au%2Crdu&mv=m&mvi=3&pl=40&initcwndbps=372500&vprv=1&mime=video%2Fwebm&gir=yes&clen=291319771&dur=1595.993&lmt=1602424298587367&mt=1643686600&fvip=3&keepalive=yes&fexp=24001373%2C24007246&c=ANDROID&txp=5535432&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIgQsEO4Y5mW0o6w77DN6i_XWvz8cDxzpCMDl-dSmYVNg0CIQCX6Evlhshum9IiDu3j5lJ3Q_DBNRhLtJcs8zZuA_unIw%3D%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRQIhAKaxI9rfL6RwLY6CHhfxjVMHcDC2rAxq5lYLqYOynyTxAiAsR8sXawG_gyI29U1ziLOI25Fd1x9vuzsuisV0zDn_wA%3D%3D"
[download] Sleeping 12.34 seconds ...
^C