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Lightning Calendar is an open-source calendar app created by Mozilla that helps you organize your schedule and events in a fully integrated calendar with your Thunderbird email.

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Lightning Calendar allows you to manage multiple calendars, create your daily to-do list, invite friends to events, and subscribe to public calendars.

Lightning Calendar is an extension to Mozilla Thunderbird, so you need to be a Thunderbird user in order to use it.

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Morgen is a multi-platform calendar platform that connects to several calendar providers and allows you to bring events together from various calendars and filter and toggle between multiple accounts.


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Google Calendar

Google Calendar for teams and individuals helps schedule meetings and events quickly and get reminders about upcoming activities.

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