From the uBO subreddit: https://old.reddit.com/r/uBlockOrigin/comments/1etvawp/youtube_ads_detection_breakages_2024_08_16_ubo/m31kbkw/

There was just an update to Quick fixes. Please test if it works for you.

1. Click Here to update the list.
2. If you disabled the list previously, enable it back.
3. Close all previously opened YT tabs and try in a new one.

Just a reminder: Please always treat disabling lists as a last resort/temporary solution type of thing. Without that list, you won’t be receiving important filter updates and will likely encounter ads after a while. So don’t keep it disabled forever - verify that it’s still necessary (daily?).

On Ubuntu I use the tar.bz2 version to not have to deal with snaps or extra repositories. Also on Debian Stable to get the latest version.