7.1. Hacks 75-83

This chapter is for people with no time and no patience. It explains how to modify the files that make up the Firefox user interface using quick-and-dirty methods.

Why would anyone want to do that? There are lots of reasons. Perhaps you're building a prototype for a demo. Perhaps you keep pressing the wrong shortcut key and you wish it were gone. Perhaps you don't like a feature, or you want to add a feature. You might be experimenting with or testing the browser, or you might need the browser to hook into something else you're testing. Finally, fiddling with the browser is a first step on the path to learning Mozilla application development.

Part of the Firefox installation is a set of files called the chrome. These are the files to which you can make quick or extensive changes. They're all human-readable, human-editable files stored on the local disk. The directories they're stored in are also called the chrome, and they're usually named chrome as well. Typically, files in the chrome have all security restrictions lifted. That presents a major opportunity to step outside the limits of web pages and create something different.

Hacking the chrome, whether cleanly or ugly, bears some resemblance to web development. There are XML, JavaScript, and CSS files to manipulate, for starters. So modifications to the chrome are particularly easy for those with web development skills.

Chapter 8 describes the preparation, coding, and bundling steps required to formally deploy a Firefox enhancement. Here, we just cut to the chase and edit files in place.