
Request URL: https://www.youtube.com/watch?v=sUfcbBgfqVE&list=LL&index=1
I suspect that the hanging is due to &list=LL part, as yt-dlp by default tries to download all items on a playlist, therefore trying to download all playlist before returning.
Solution: add noplaylist option to yt-dlp parameters. https://github.com/yt-dlp/yt-dlp/blob/54a63e80af82791d2f0985bd0176bb182963fd5f/yt_dlp/YoutubeDL.py#L302
Thanks.