"In 2025, YouTube started rolling out a new streaming protocol, known as SABR, which breaks down the video into smaller chunks whose internal URLs dynamically change rather than provide one whole static URL. This is problematic because it prevents downloaders (such as yt-dlp) from being able to download YouTube videos at resolutions higher than 360p due to only detecting format code 18 (which is the only format code available that doesn't use SABR). So far, this issue has only affected the web client, so one workaround would be to use a different client, such as tv_embedded (where SABR has not yet been rolled out to), so for instance in yt-dlp you could add --extractor-args "youtube:player_client=tv_embedded" to use that client. It is not known how long this workaround will work as intended, as YouTube rolls out SABR to more and more clients."

https://wiki.archiveteam.org/index.php/YouTube/Technical_det...

Thanks for the comment, OP just throwing out just "SABR" like we're all supposed to know what it means.