IceCat is the GNU version of Firefox for Linux and other free operating systems. Iceweasel is functionally identical to Firefox it just has a different name and logo. Mozilla won’t allow Debian to package and tweak their own version of Firefox without calling it something different, so Iceweasel was born. If you’re using Debian Linux, you probably have Iceweasel installed instead of Firefox. If you long for the days of Mozilla, you can use SeaMonkey, the successor to the full Mozilla suite.
These features were ripped out of Firefox to make it a more focused, speedy Web browser. Firefox was the evolution of the “Mozilla Application Suite,” which also contained email, IRC chat, HTML-editing, and newsgroup capabilities. SeaMonkey isn’t technically based on Firefox, but it’s closely related. It also uses its own configuration directory, unlike Waterfox. Pale Moon diverges from Firefox in removing accessibility and parental control options, while modifying the default interface settings to be similar to earlier versions of Firefox - it has a bookmark toolbar and status bar by default. Pale Moon is another “optimized” build of Firefox for Windows, but it also has a 32-bit version. If you decide to uninstall it, don’t select the “Remove my personal data” option unless you also want to delete your Firefox data. Waterfox uses the same profile data Firefox does, so switching to Waterfox is easy.
