Beta or prerelease software is not intended for inexperienced users, as the software may contain bugs or may potentially damage your system. We strongly recommend that users exercise caution and save all mission-critical data before installing or using this software.
Mozilla Thunderbird Beta (Linux) is intended for developers and members of our testing community to use for evaluation and feedback. The beta version features fixes when importing email from Microsoft Outlook and default mail client check now works with newer Linux distributions.
Full Specifications
What's new in version 82.0b3
MailExtensions: API for running content scripts on displayed messages
MailExtensions: browser.tabs.sendMessage API added
Chat icons updated
MailExtensions: compose.begin functions now support creating a message with attachments