YouTube is experimenting with blocking ad blockers, presenting some users with a dialog saying ad blockers are not allowed.

Reddit user Sazk100 posted a screenshot of a YouTube dialog saying: “Ad blockers are not allowed on YouTube.” The dialog then goes on to say that ads are what keeps YouTube free, and that uses can opt for YouTube Premium to avoid ads while still supporting creators.

One of the YouTube Reddit moderators, LightCodeGaming, replied and said a YouTube employee had reached out, confirming this is an experiment the company is conducting:

Yes, this has been confirmed as an experiment by YouTube, confirmed by a YouTube employee that reached out to me.

It’s not surprising that YouTube is trying to crack down on ad blockers. YouTube and Google both make a large portion of their revenue via ads. While this may still be an experiment, it will likely pave the way for some type of anti-ad blocking measure.