ThunderBird is Mozilla's free open source email management application, similar to Microsoft Outlook.
Like other Mozilla products, ThunderBird is an open source free software, ThunderBird is known not only for its free, but also for its efficiency and quick use. Of course, ThunderBird is not able to bring all the powerful features that Microsoft Outlook currently has, but Mozilla's efforts for a free internet community are always welcomed by internet users.
Mozilla Firefox is currently under great pressure from Google's Chrome browser.
Perhaps the difficulties of maintaining and ensuring the security of Thunderbird are the main reasons Mozilla has given up on continuing to develop this application. Currently Mozilla is focusing its resources to hit hard on the mobile platform when the main product Firefox is currently facing many difficulties with too strong competition from Chrome.