Calendar and Date/Time
Lightning Requires Restart
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.
Send Later Requires Restart
True "Send Later" functionality to schedule the time for sending an email.
TbSync (Provider for Exchange ActiveSync) Requires Restart
Synchronize Exchange ActiveSync accounts (contacts, tasks and calendars) to Thunderbird, supports Office 365, Outlook.com, Freenet, Strato, Hotmail, Kopano and other EAS compatible servers.
Lightning Calendar Tabs Requires Restart
Displays tabs which allows quick navigation between time periods in Lightning calendar. All views of calendar are supported. Color of tab texts can be adjusted.
Lightning Colors Reminder Requires Restart
Let's show the calendar color on Lightning reminders!
G-Hub Lite Requires Restart
Add Google Tabs to Thunderbird! Services supported: Voice, Calendar, Drive, Docs, Sheets, Slides, Hangouts, Plus, Photos, Contacts, News, Maps, & many more. Need Google Apps? Check out G-Hub Pro: http://www.schiffner.com/index.php/software/g-hub-pro
lightningWeather Requires Restart
LightningWeather shows the weather forecast in the background of the calendar so you can easily coordinate your activities with the weather.
The 'NoiaButtons' add-on offers cartoonish toolbar button icons (known from Noia themes) for default theme and lightweight themes. Further more lite silver and dark versions of Noia themes are included.
Lightning Invitation Notifier Requires Restart
This extension is an extension to Mozilla Lightning for Thunderbird.
It shows a toast message and opens the invitations window when an invitation arrives.
AdvancedTasks Requires Restart
Thunderbirds Lightning Extension: Allows the use of Markdown in Task descriptions and renders them as HTML in the TaskView.
EDS Calendar Integration Requires Restart
Integrates calendars events with Gnome clock applet
Plugin may hang on Fedora.
As a workaround uninstall evolution-ews.
Todo.txt Extension Requires Restart
Thunderbird extension for the Todo.txt application
Lightning Reminder Left Buttons Requires Restart
Tired to mistakenly press that "Dismiss All" button? Move the Lightining Reminder "Snooze all for" and "Dismiss All" buttons to the LEFT!
... and from version 2.0 you can keep them on the RIGHT, but swapped!
LCD Clock Requires Restart
displays a LCD Clock in your Toolbar
Show Calendar Week Requires Restart
Shows the calendar week Thunderbird/Lightning calendar's moth and multi-week view.
Purge Events Plus Requires Restart
Purge events from Sunbird and Lightning files and thereby cleanes the calendar
This plugin adds our savvy email templates to your Thunderbird toolbar.
NirvanaHQ Requires Restart
NirvanaHQ for Thunderbird
MultiBirthdaysReminder Requires Restart
This addon is now integrated into the new address book CardBook and thus it is no longer maintained
StormCows Requires Restart
Allows two-way access between Remember The Milk and calendar events or todo items.