Lightning Extension for Mozilla Thunderbird - Smooth Integration of Calendar and Tasks Functionality

Lightning Extension for Mozilla Thunderbird - Smooth Integration of Calendar and Tasks Functionality
Page content


Mozilla Lightning is a polished calendar/scheduling extension for Mozilla Thunderbird. First released in March 2006, the extension has been through numerous changes and lots of feature additions. As of today, the latest stable version is 0.9, which is available from Mozilla’s add-ons site. The 1.0 release will be released as a built-in feature in Mozilla Thunderbird3, which makes 0.9 the last standalone extension release for Thunderbird2. Although it cannot rival Microsoft Outlook at the number of features available, it is slowly getting there inch-by-inch, version-by-version. Here are some of the major features it has in the latest version:

  • Free, Open-Source, Cross-Platform
  • iCalendar compatible
  • CalDAV compatible
  • Support for email invitation (iMip/iTip) standard
  • Easily extensible

To install the add-on, make your way to Mozilla’s Add-ons site and navigate to the Lightning extension. After downloading it, you should have a .xpi file. Just run Thunderbird and open the Add-ons window from the Tools menu. Drag this xpi file into that window. Once installed, Thunderbird will ask you for a restart. Accept that and you will be able to use Lightning after it starts up.


As soon as Thunderbird starts up, you will see a few extra buttons on the bottom-left corner of Thunderbird - Calendar and Tasks. Clicking either button will take you to its respective view, Day or Week. Since the calendar is new, it’ll be pretty empty. You can import a calendar if you’ve been maintaining one elsewhere.

Lightning supports importing of iCal-compatible .ics files, and comma-separated value files (.csv). Almost all web-based and standalone calendar applications should allow you to export your calendars to at least one of these formats. Just click on File > Import Calendar to import it. After it’s done importing, you will be able to view your appointments and calendar entries using whatever view you prefer (Day/Week/Month).

new event

Adding new entries is as easy as right-clicking on the appropriate date and selecting “New Event”. It will open a small window where you will be able to specify how you want to store it. You can send invitations using the “Invite Attendees” button at the top. The description you type in will be sent as the message text to all recipients. You can also convert emails into calendar entries. If the email mentions a date, it will be taken as the meeting/appointment date. And you can also turn a calendar entry into an email. The integration with Thunderbird is very slick.

You can also publish this calendar online at compatible services like Google Calendar, 30 Boxes, etc. This will keep it synchronized between the two services, so you don’t have to lug around your laptop everywhere. As long as you have Internet access, you can access your calendar online and make changes to it. All you have to do is right-click on the calendar and select “Reload Remote Calendars”, which will synchronize your calendars between the two services.


The tasks functionality allows you to save handy one-liners to make sure you remember your day’s chores, appointments, dates, etc. You can set priorities to tasks and set incremental levels of completion to every task, and set it in specific categories.


For now, there is no capability of syncing your tasks online with similar services like GMail’s tasks. Also, exporting the calendar does not include tasks. You have to export them separately. As with the calendar, you can convert your mails into tasks and vice-versa.

Final Words

As you have seen above, Lightning is a very useful tool for everyone who maintains calendars and wants something cross-platform which can work from anywhere. The integration with Thunderbird is certainly going in the right direction, and with the bundling in of the 1.0 release into Thunderbird3 itself, good things are expected from this slick extension.