What browser are you using? [poll]

There are many additional plugins available for any browser. This is not a key feature.
I also use Firefox, and its most useful and convenient features for me, besides tabs and extensions, are: the ability to find any visited website by entering just one letter of its name or title, and the ability to bind any search bar on any website to a specific key or key combination, allowing you to enter the search query directly into the address bar.