globalChrome.css Requires Restart
Provides global user stylesheet.
MinimizeToTray revived Requires Restart
Minimizes windows into the system tray.
When you press the middle mouse button or scroll wheel mouse show popup window the history in the url bar and search bar.
ToggleDocumentColors_ Requires Restart
Adds a toolbar button and keyboard shortcut to switch between the default page colors and user-defined colors.
Firefox shortcut: Control-Shift-C
SeaMonkey shortcut: Control-K
Restart Application Button lets you restart your Firefox and SeaMonkey application by a quick toolbar button click.
SanRockstar Requires Restart
ImageBlock for seamonkey Requires Restart
Updated version of imageblock by Hemant Vats to work with seamonkey 2.29.
Provides a fast way to disable images in web pages that's usually set by the image manager sub-menu.
Splash! (Compatible version of Firefox 4) Requires Restart
Adds a splash screen. Supported in Firefox, Flock, Thunderbird, Sunbird, eMusic Remote, Songbird and Sunbird.
Changes the mask character used in password fields.
KeePass Helper Requires Restart
Adds a hostname, URL, or email account ID to the application's window name (e.g., that of Firefox or Thunderbird) to make it recognizable to password manager utilities like KeePass.
HTitle (discontinued) Requires Restart
Hide title bar if window is maximized.
This add-on has been discontinued!
Legacy extensions support will be dropped in Firefox 57. If you interest in CSD on Linux, please track progress on https://bugzilla.mozilla.org/show_bug.cgi?id=1283299.
Xclear Requires Restart
Safari-like icons in the URL, search and find fields to clear their contents.
Transform the colors of entire web pages or selected elements. Combine predefined themes with basic transforms. Save transforms for specific web domains.
Generic CSS Loader 2 Requires Restart
A very basic CSS loader for Firefox. No fancy features, just an alternative to userChrome and userContent files.
Link Status Requires Restart
Shows an icon on the status bar when the mouse cursor is over a link to a page you bookmarked or visited before. In Firefox 3.5 and later, the extension also offers an option to disable the visited link styling to reduce the risk to privacy.
Download every YouTube video you want and you can download them as Full HD MP4, FLV, 3GP, MP3, M4A and AAC formats.
This addon returns the old view of the pop-up notifications, as in Firefox 4.0 - 43.0
Personasizer allows you to expose more of your persona's header image. Useful for personas that have text or an important part of their content cut off by the browser's navigation elements.
Colorize entire web pages. Configure themes using sliders and drag-and-drop. Set domain preferences for automatic coloration.
Scriptish Requires Restart
The greatest user script engine on the Internet (a fork of Greasemonkey).