$ yt-dlp --cookies-from-browser=firefox:/Users/brett/Library/Application\ Support/Firefox/Profiles/82zjhi8h.default-1409182587484 https://www.bbcmaestro.com/courses/alan-moore/storytelling/lessons/alan-s-introduction -vU
[debug] Command-line config: ['--cookies-from-browser=firefox:/Users/brett/Library/Application Support/Firefox/Profiles/82zjhi8h.default-1409182587484', 'https://www.bbcmaestro.com/courses/alan-moore/storytelling/lessons/alan-s-introduction', '-vU']
[Cookies] Extracting cookies from firefox
[debug] Extracting cookies from: "/Users/x/Library/Application Support/Firefox/Profiles/82zjhi8h.default-1409182587484/cookies.sqlite"
[Cookies] Extracted 1865 cookies from firefox
[debug] Encodings: locale UTF-8, fs utf-8, out utf-8, err utf-8, pref UTF-8
[debug] yt-dlp version 2022.04.08 [7884ade] (mac_exe)
[debug] Python version 3.8.9 (CPython 64bit) - macOS-12.3.1-arm64-arm-64bit
[debug] Checking exe version: ffmpeg -bsfs
[debug] Checking exe version: ffprobe -bsfs
[debug] exe versions: ffmpeg 5.0 (setts), ffprobe 5.0, rtmpdump 2.4
[debug] Optional libraries: brotli, certifi, Cryptodome, mutagen, sqlite, websockets
[debug] Proxy map: {}
Latest version: 2022.04.08, Current version: 2022.04.08
yt-dlp is up to date (2022.04.08)
[debug] [generic] Extracting URL: https://www.bbcmaestro.com/courses/alan-moore/storytelling/lessons/alan-s-introduction
[generic] alan-s-introduction: Requesting header
[redirect] Following redirect to https://www.bbcmaestro.com/courses/alan-moore/storytelling
[debug] [generic] Extracting URL: https://www.bbcmaestro.com/courses/alan-moore/storytelling
[generic] storytelling: Requesting header
WARNING: [generic] Falling back on generic information extractor.
[generic] storytelling: Downloading webpage
[generic] storytelling: Extracting information
[debug] Looking for video embeds
ERROR: Unsupported URL: https://www.bbcmaestro.com/courses/alan-moore/storytelling
Traceback (most recent call last):
  File "yt_dlp/YoutubeDL.py", line 1408, in wrapper
  File "yt_dlp/YoutubeDL.py", line 1478, in __extract_info
  File "yt_dlp/extractor/common.py", line 641, in extract
  File "yt_dlp/extractor/generic.py", line 4039, in _real_extract
yt_dlp.utils.UnsupportedError: Unsupported URL: https://www.bbcmaestro.com/courses/alan-moore/storytelling