Excellent and free! Adblock Plus is efficient and catches almost everything. If an add comes through you can click on the ADP icon on the tab bar on Foxfire and select "Report issue on this page" so they can add the URL, etc of that advert to their list, within a day or two, sometimes even faster, that ad is blocked. I also donate a small amount of money to Adblock Plus every year to thank them for their great work. Remember that the point of freeware and shareware, as well as a free and open internet takes community. I would rather give $10/year to Wikipedia, Mozilla, Adblock Plus and other sites offering great services and caring about a free internet than to spend my money with a huge uncaring multi-national corporation that cares only for its bottom line. So thank you Mozilla, so much, and thank you Adblock Plus.