YouTube is currently experimenting with server-side ad injection. This means that the ad is being added directly into the video stream.
This breaks sponsorblock since now all timestamps are offset by the ad times.
For now, I set up the server to detect when someone is submitting from a browser with this happening and rejecting the submission to prevent the database from getting filled with incorrect submissions.
yeah that makes sense. i was thinking maybe youtube had servers to decide what chunks clients would get, maybe by looking at whether or not they are premium users first. but anyway youtube still needs a way to differentiate between ad chunks and video chunks, otherwise we would just be able to skip 10 seconds through all the ads. surely that can be exploited somehow.