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Your calendars will be color-coded to distinguish between them in the main calendar views, and you can show or hide them by toggling the check box in the left-hand sidebar’s list. You can gain even more flexibility by adding additional calendars, to track work and group events separately, for example. By default, you have just one: “Home.” You can add events to this calendar as desired with the New Event button–Lightning supports single and repeating events, timed and all-day events, user-defined event categories, adjustable privacy levels, automatic reminders, and sending invitation requests to people in your address book. In the calendar view, the left-hand sidebar holds a small month-view widget and a list of all of the available calendars tied to your profile.
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The bottom left-hand corner of the window contains an application switcher, so you can jump between the calendar view, your email, and the task list organizer. When you restart Thunderbird, you will see the calendar components built right into the user interface and menus. Inside Thunderbird, select the Add-ons manager from the Tools menu, hit the Install button, and select the newly-downloaded XPI. You can install the Lightning extension by downloading the XPI file from the extension’s page at. The stand-alone version of the calendar is called Sunbird, but most users choose the Lightning build instead, an extension for Thunderbird that integrates calendar functions into the email client.
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The third but perhaps least-known application in the Mozilla suite is the Mozilla calendar client–a cross-platform tool for managing multiple local and remote calendars, tracking to-do tasks, and synchronizing with other users.
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The project applied the same development model to building its email client Thunderbird, which shares many of the same underlying technologies and design principles used in Firefox. The Mozilla project is best known for its widespread Firefox browser, a cross-platform, extensible, and open source Web tool used by millions.
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