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SeaTab-X-2 Requires Restart

Adds Firefox-style tab closers into SeaMonkey.

Rated 5 out of 5 stars (22)
1,015 users

Element Hiding Helper for Adblock Plus

Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.

Rated 5 out of 5 stars (473)
932 users

SeaMonkey Debug and QA UI Requires Restart

Provides Additional Debug and QA UI for SeaMonkey development and testing.

Rated 3 out of 5 stars (3)
929 users

Theme Font & Size Changer for ThunderBird

Theme Font & Size Changer lets you change the global font size and font family used for the user interface in Firefox. Design your browser with your favorite font.

Rated 3 out of 5 stars (100)
912 users

Header Tools Lite Requires Restart

Allows to modify the header and the source of messages

Rated 4 out of 5 stars (45)
912 users

ThunderBirthDay Requires Restart

Display birthdays from the Thunderbird addressbooks as events in Lightning.

Rated 4 out of 5 stars (97)
900 users

DownThemAll! Featured

The first and only download manager/accelerator built inside Firefox!

Rated 4 out of 5 stars (2,896)
874 users

Lightbird Requires Restart

Standalone calendar UI for Lightning

Rated 4 out of 5 stars (21)
812 users

Bluhell Firewall

Get a faster browsing experience by blocking nasty web resources using Bluhell Firewall, the lightweight Ad-Blocker and Tracking/Privacy Protector.

Rated 4 out of 5 stars (497)
784 users

Image Zoom Requires Restart

Adds zoom and rotation functionality for images...

Rated 4 out of 5 stars (355)
774 users

FireFTP Requires Restart

FireFTP is a free, secure, cross-platform FTP/SFTP client for Waterfox which provides easy and intuitive access to FTP/SFTP servers.

Check out my new project, FireSSH!

Rated 4 out of 5 stars (1,067)
773 users

P7MON Requires Restart

Abilita la gestione alternativa degli allegati P7M

Rated 5 out of 5 stars (2)
742 users

Speed Start

Speed Dial & Start Page with flexible layout for fast access to sites via visual bookmarks

Rated 5 out of 5 stars (80)
708 users

Saved Password Editor Requires Restart

Adds the ability to create and edit entries in the password manager.

Rated 5 out of 5 stars (389)
674 users

Awesome ldapInfoShow

Show contact photo and other info from Local Dir, Addressbook, LDAP, Facebook, LinkedIn, Flickr, Gravatar etc

Rated 4 out of 5 stars (14)
667 users

Extra Format Buttons Requires Restart

Adds a font size (in pixels), strikethough, subscript and superscript buttons to Thunderbird's Compose Window.

Rated 4 out of 5 stars (19)
658 users

GNOMErunner Options Requires Restart

Allows to customize GNOMErunner theme

Not yet rated
594 users

Flexible Identity Requires Restart

Selects an identity based on the recipients list when sending an email

Rated 4 out of 5 stars (39)
563 users

PDF Viewer for SeaMonkey

A fork of PDF.js with support for SeaMonkey 2.49.x.

Rated 5 out of 5 stars (2)
533 users

Return Receipt Toolbar Button Requires Restart

Allow you to add a Return Receipt button to mail compose window toolbar.

Rated 5 out of 5 stars (20)
508 users