About protocol links

There are a few special strings, which begin with about:, that you can type into your Location Bar.

They are listed in Mozilla source here.

• about: — Same page as Help > About.
• about:about — Not used any more. It may have, at one point, listed all these about: URLs.
• about:blank — A blank page. Useful for setting as your homepage.
• about:bloat — Unknown. (trunk mozilla builds?)
• about:buildconfig — Reveals details about how your Mozilla build was compiled.
• about:cache — See cache statistics and browse the cache.
• about:cache-entry — Shows information about a cache entry. Used in about:cache links. Requires params.
• about:config — GUI for modifying user preferences (prefs.js).
• about:credits — Contributors, developers, and more.
• about:logo — Displays the Mozilla logo. (Mozilla Suite only).
• about:kitchensink — Only appeared for a short time. Still viewable from the patches on the bug.
• about:mozilla — The famous Book of Mozilla.
• about:plugins — Lists all your plugins as well as other useful information.

Extensions

Firefox extensions add a few additional about: URIs, namely:

• Firesomething adds two excerpts from The Book of Mozilla, Extended edition, available at about:firefox and about:firesomething.
• InfoLister adds about:info — listing of your extensions, themes and plugins.