Most Popular Extensions
CapsKiller Requires Restart
Caps Killer is a protection against newbies using caps in their mails.
Perapera Japanese-German Dictionary File Requires Restart
This is additional dictionary file for use with the Perapera Japanese Pop-up Dictionary add-on.
DHS Facebook Unblock Requires Restart
Plugin to get around the Washtenaw County Facebook block.
Lovebird Requires Restart
Email organized around the people you care about.
Lightning Multiweek View Requires Restart
Adds a multiweek view to...
manoderecha Requires Restart
Assists to setup a chat account for manoderecha
Spoof Detector Requires Restart
Extension for Email Spoofing Detection
NetscapeCommunicator 4.x Account Settings Migrator Requires Restart
Provies ability to migrates account settings and preferences from NC4.x profiles.
After Unsent Mail Is Sent Requires Restart
Run a program of your choice after unsent mail has been sent.
Provides button to copy the list of current reminders to the clipboard.
Lowercase Email Addresses in Message Headers Requires Restart
Shows lowercase email addresses in message headers and their tooltips.
Seturgent Requires Restart
Sets the urgent flag (X11) of the Thunderbird window under Linux in case of new messages. Does ignore special folders like Drafts, Junk and such.
Mark Read On Reply Requires Restart
A simple extension to mark messages read after you click a reply menu or button (or Ctrl+R)
Shift Box Requires Restart
Replay your INBOX!
Markov Dictionary Switcher Requires Restart
Based on Dictionary Switcher but more than a thousand times faster and you can choose dictionaries that you want to use. Detects the language of the message that you are composing and changes the spelling dictionary.
Nightly Tester Tools Lite Requires Restart
This is a cut down version of Nightly Tester Tools by Mossop, which is 77.6 KB. I've only included the "copy build id" and "build id in titlebar"...
World Weather Requires Restart
Display local weather information from around the...
PasteIP Requires Restart
Easy pasting of your IP address or User-Agent in a textbox. Comes in handy when posting on forums, etc.
Workspace for Thunderbird Requires Restart
A simple editor for executing snippets of JS. In Thunderbird.