This extension will attempt to steal your Facebook AD account details on install, including your API token. There are hundreds of Browser Hijackers around the web and the Hide YouTube Comments is certainly not the only one that you will meet. The essential thing to remember about this type of programs is to never click and explore any of the pop-ups they display. In case you are being spammed with ads related to specific items that you would like or that you've bought recently, then this is most likely because the Hide YouTube Comments has read throughout the registry files, kept in your browser, and has acquired information about your recent Internet searches. Quite a lot of organizations collect data using this method - Google itself is known for doing it - but at least these companies are public and have a popularity to defend against a scandal. Browser Hijacker developers are usually small and unknown, giving them the power to sell and resell the information that they have acquired from you to whoever is interested in paying for it. Another thing to be aware of is that not every advert, displayed by the hijacker, is reliable. The possibility of opening something dangerous is high - you could lose your money on a low-quality product that doesn’t actually work or worse. That’s why it is just better to remove the unwanted program as soon as possible.