The Firefox 1.5 CCK can be used to create an extension that customizes Firefox. It allows the following customizations: • Add identifer to the user agent string • Change the default home page and startup override home page • Change the title bar text • Change the animated logo • Change the web page and tooltip used for the animated logo • Add a help menu item that links to a web page • Provide sites for which popups and XPInstalls are allowed by default • Preinstall browser plug-ins • Preinstall search engines • Add folders, bookmarks and live bookmarks to the personal toolbar • Add folders, bookmarks and live bookmarks to the bookmarks folder • Set default preferences • Lock preferences • Add registry keys (Windows only) • Add certificates (See NOTE below) • Set default proxy configurations • Package other XPIs with your distribution • Disable about:config