Because you probably use your browser more than any other program on your computer, it would be nothing short of criminal to make you use a browser you didn't love. So think of the default Firefox setup as a mere suggestion. It's the developers' best guess as to what a Web browser should be, but it certainly isn't the only way to go. Perhaps you want this button over there or that menu gone entirely. Perhaps Firefox is missing a feature you need, or maybe you just think it looks better in black. Whatever your fancy, anything is possible thanks to the extensive customization features I outline in this part.