For those who have a comprehensive calendar such as Outlook is missing in the Thunderbird email client there is the free Lightning extension. This can be within this open-source email-client appointments are managed.
Mozilla Lightning is a calendar extension for the email client Mozilla Thunderbird. The extension is just like Thunderbird, developed by the Mozilla Foundation, this organization is also the creator of the wildly popular Firefox browser.
Because Mozilla Lightning is an extension, it is integrated in the email client, this is in contrast to the other calendar application from Mozilla: the Sunbird. Therefore, it is with Lightning as possible, to calendar functions directly in the Thunderbird user interface to manage it.
By integrating Lightning with Thunderbird, can this combination for both individuals and organisations a free alternative to Microsoft Outlook.
Mozilla Lightning has the following features:
Mozilla Lightning screenshots
You can free download Lightning and safe install the latest trial or new full version for Windows 10 (x32, 64 bit) from the official site.