YouTube tests stealth ads to bypass blockers and boost revenue

YouTube has not widely publicised this issue, and the first reports on these experiments are from an unexpected source. As noted by 9to5Google, the problem recently came to light for a developer of the SponsorBlock extension, which allows users to skip parts of videos marked as sponsored content. It turns out that with these injected ads, the extension cannot function properly because the timestamps are not adjusted according to the length of the ad.

For most users, however, it's probably more important to know that ad injection has a different goal than disrupting (intentionally or not) the functionality of sponsored content skippers. The purpose of ads added server-side is to be technically indistinguishable from other streaming elements and thereby unrecognisable and unblockable by ad blockers, which YouTube has been fighting intensively recently.

Currently, server-side ad insertion is likely still in the testing phase. Once implemented widely, YouTube is expected to announce this change and use it as an opportunity to encourage users to subscribe to Premium or accept the ads—as that is the ultimate goal.

It is worth noting that long, non-skippable ads appear more frequently in YouTube videos, often at random points during the video. Since last November, video creators have had limited control over ad configurations. YouTube introduced artificial intelligence into the process, which handles the details so creators can "focus on the videos".