Opera 21 relies on third party extensions for extra functionality. When add-on type items are built into the basic browser, they complicate the browser, and many people do not need or want the feature. The new model is for people who want the download to get the add-on -- not for all users of Opera to have a feature, many don't need or want. If you don't want any extensions, you might want to consider staying with Opera 12 (which has a lot of add-on type features) thrown into the browser, or go with Opera 21 for its leanness, speed, and the way it accesses sites better (and not worry about every feature you once had in Opera 12 that is no longer there. It's a choice to be made if you won't consider extensions. Now I use Ad-block plus with Opera 21, and find it great. I believe the company that makes it, EyeoGmbH also provide that extension to Firefox and Chrome, and seem to have excellent experience and expertise in the area of ad-blocking. Here's a something about adblock (which is open source and has different ownership from AdBlock plus) http://en.wikipedia.org/wiki/AdBlock and a faq on ad-block plus that you may find helpful. https://adblockplus.org/en/about Third Party doesn't necessarily mean something is bad.