Ice Weasel is a Firefox modified by Debian maintainers.<p>It's actually a good thing that they couldn't use the Firefox trademark ... since its rendering has been broken since a year ago when I first installed it (some problem related to Cairo or something like that) ... while Firefox downloaded from the official website worked fine.<p>Not to mention that a lot of people get tricked into buying open-source software through various shareware websites, and the big problem with such services would be that browsers like Firefox get "enhanced" with spyware abilities, while branded as "Firefox". Such actions diminish the trust of users in the brand, so Mozilla has to have a way to prevent that.