It is not ads, it is a notification on tutorial videos about the extension on the official YouTube channel https://www.youtube.com/@PocketTubeHQ/videos which you can see in the extension description too. I have been developing it for over 5 years. The extension has Recommended label and over 200K users in Chrome, and no one put the sort of comment. I'm making tutorial videos on every update, it is a lot of work, and my users are happy with it because they know about updates and how exactly its use.