Some web sites that I want to use result in a new Firefox window advertising something I have no interest in. Here is an example of a URL from a window that I often see http://www.partypoker.com/td/videopop/video-poker-game.htm?wm=3302290 These often provoke my Avast anti virus s/w to report it has deleted something threatening. What I would like is a black list facility that has a button like the bookmark one but allows me to tell Firefox I have no interest in new windows/tabs/popups from the site in the current URL which results in Firefox deleting anything that arrives from the site without displaying it or allowing it to do anything on my PC.