Duplicate Tab Requires Restart
Duplicate Tab allows you to clone a tab along with its...
Want to change from one language to another? Zing! and the locale is switched.
CloseTab Requires Restart
Lightweight add-on which adds to right-click menu 3 items allowing to close current tab, open a new one and reopen closed one. Right-click anywhere on site instead of using keyboard or finding buttons.
NiceReader Requires Restart
NiceReader is designed for web reading. You can customize font, color, size, background, specify the elements to read, filiter ad elements, filiter ad strings, automaticaly turn page.
MonkeyFix Requires Restart
Fixes up numerous SeaMonkey browser interface issues (eg. adding support for popup ALT attributes), as well as adding some handy features for developers and power users (eg. configure source viewer, work online/offline).
TaQuilla Requires Restart
Automatic tagging using Bayesian statistics
Adds a few buttons to help with page navigation, including Page Top, Page Bottom, Page Down and Page Up.
FAYT Revived Requires Restart
Regain possesion of your good "Find As You Type" search bar in Firefox and SeaMonkey!
A full featured color selector tool, to work with colors, and easily find the colors you want.
Remember Mismatched Domains Requires Restart
The Remember Mismatched Domains extension for Firefox and Thunderbird adds a "Don't warn me again about this certificate for this domain" checkbox to the Domain Mismatch and Expired Certificate warning windows. When selected the domain...
Hide the caption of Firefox
From/To Column Requires Restart
Add a “From/To” column which shows the recipient if you are the sender.
Zorcher Requires Restart
Selecting a small text on the page do not need to copy it into the search bar of your browser or search engine. Just press the right mouse button and select the search service from the available list.
Tab Clicking Options Requires Restart
Select actions for various clicking events on a tab or the tab...
Dynamic creation of bookmark-style toolbar buttons which you can customize.
SeaMonkey Vertical Tab Bar Requires Restart
Tab bar on the side of the window for SeaMonkey.
Makes every page to have light text on dark background (exact colors are customizable)
Firefox version is here: https://addons.mozilla.org/firefox/addon/dark-background-light-text/
Tategaki Requires Restart
Tategaki allows vertical writing-mode on mail compose window.
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.
Changes the mask character used in password fields.