1 091 875 gebruikers
Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.
287 032 gebruikers
Allows bidirectional access to Google Calendar
147 054 gebruikers
OpenPGP message encryption and authentication for Thunderbird and SeaMonkey.
166 782 gebruikers
LookOut is a plugin which allows Thunderbird to interface with Microsoft's mail tools by decoding metadata and attachments encapsulated/embedded in a TNEF encoded attachment (aka winmail.dat).
136 844 gebruikers
ReminderFox displays and manages lists of reminders and ToDo's. ReminderFox makes sure you remember all of your important dates via easy-to-use lists, alerts, and alarms, right in your browser without the need for a separate calendar program.
78 941 gebruikers
This addon provides a conversation view for Thunderbird, grouping messages together and allowing you to reply "inline" thus providing a more efficient workflow.
The latest version is compatible with Thunderbird 24+ only (see below for details).
118 934 gebruikers
Help make Firefox better. The Add-on Compatibility Reporter enables you to report if the Firefox add-ons that you're using are working properly.
198 746 gebruikers
This extension is for those TB3 users who want the multiple-columns view that TB2 allowed
42 663 gebruikers
True "Send Later" functionality to schedule the time for sending an email.
87 636 gebruikers
Switch the signature on/off or choose a new one from your predefined set...
70 995 gebruikers
Quicktext is an extension for Thunderbird that lets you create templates that can be easily inserted into your own emails.
51 122 gebruikers
Google and Zimbra contact sync for Thunderbird. (TB 24 and above NOT supported)
53 988 gebruikers
Useful tools for the nightly tester.
61 373 gebruikers
Search and remove messages which are the same as other messages in your mail folders (referred to as duplicates or dupes).