UBO updates their filters when they can, as they find and fix changes.

Youtube directly responds to those patches by updating their system. Last I checked, they do this twice a day.

Any time your UBO isnt stopping youtube, you are using filters from before youtubes last update. Opening your UBO settings, clearing and updating your filters, and refreshing your browser fixes this.

The only time it doesnt is if UBO hasnt patched youtubes most recent changes. This window of time is teeeny tiny.