Lightning Calendar

Thunderbird is an open source project, which means anyone can contribute ideas, designs, code, and time helping fellow users.

Experience cutting edge features. Provide feedback to help refine and polish what will be in the final release.

Help us test the newest developments made to Thunderbird every day by using the unstable Nightly channel.

WARNING! Nightly is an unstable testing and development platform, make sure you back up important data regularly!