One issue with ad-blocking, or in fact any other addon which may be user-configured, is that they may produce browsers which have a unique fingerprint, which wi

One issue with ad-blocking, or in fact any other addon which may be user-configured, is that they may produce browsers which have a unique fingerprint, which will undermine any anonymity offered by Tor. It's important that all installations of an anonymity software offer the same, or a restricted number of fingerprints, and they restrict the ability of the user to modify it by mistake. Also, eliminating the surface area for fingerprinting a browser is useful - so for example, removing flash (which can fingerprint you based on installed fonts), having NoScript enabled, and having a default web-bug blocking setup (such as disconnect.me), and self-destructing cookies should be a must.