Firefox’s interface is cleverly designed using JavaScript and XUL, and using what’s referred to as chrome URL’s you can actually open specific windows in a tab or the sidebar. This includes things like the management windows for bookmarks, saved passwords, downloads, extensions, and more. They can even be bookmarked for quick one-click access to them in the future.

Below we’ve got our top 5 chrome URL’s that can be used in Firefox 3, and all you have to do is copy the URL into the address bar to see what each of them do. Don’t forget to bookmark the ones that you’ll use frequently, and here are some instructions if you want them to open in the sidebar.

Note: The URL’s will obviously only work in Firefox.

1) Bookmarks Management

Used for: Managing bookmarks, tags, and history.
URL: chrome://browser/content/places/places.xul

firefox chrome bookmarks-2.png

2) Downloads

Used for: Managing past and active downloads.
URL: chrome://mozapps/content/downloads/downloads.xul

firefox chrome downloads.png

3) Extensions

Used for: Enabling, disabling, and uninstalling extensions, themes, and plugins.
URL: chrome://mozapps/content/extensions/extensions.xul

firefox chrome extensions.png

4) Saved Passwords

Used for: Managing passwords stored by Firefox.
URL: chrome://passwordmgr/content/passwordManager.xul

firefox chrome saved passwords-1.png

5) Preferences

Used for: Configuring different options in the browser.
URL: chrome://browser/content/preferences/preferences.xul

firefox chrome preferences.png

Runner Up: Browser inside a Browser

Used for: Displaying a browser inside a browser. This is more for fun than anything else.
URL: chrome://browser/content/browser.xul

firefox chrome browser.png

[via Firefox Facts]