A free and open source email, newsfeed, chat, and calendaring client that is easy to set up.
Publisher’s description
What is Mozilla Thunderbird Beta (MSIX)?
Mozilla Thunderbird Beta (MSIX) by Mozilla is open-source Windows software in the chat & messaging category.
Installation and requirements
The publisher provides MSIX installers for 64-bit Windows. The main installer is 152.6 MB. It needs Windows 10 1809 or newer. A silent install is possible with the installer’s documented switches.
Pros / Cons
Pros
- Open source: the code can be inspected and built by anyone
- Documented silent install
Cons
- No native ARM64 build
In short: Mozilla Thunderbird Beta (MSIX) is an open-source chat & messaging tool for 64-bit PCs. Administrators can deploy it unattended.
Is Mozilla Thunderbird Beta (MSIX) safe to download?
- The file is served by archive.mozilla.org, the publisher’s own domain
- The download link uses HTTPS
- A SHA256 hash is published, so you can verify the file:
0675FB2B4C151DA531913DE9B476607B882F6B24D9565A3D29720505FD4AE4CA· Open the VirusTotal report for this hash - The link answered when we last checked it (October 22, 2026)
- The source code is public
- ExeAtlas does not host, wrap or modify installers
Related guide: How to check a file’s SHA256 hash on Windows
Recent versions
All 1 versions ›| Version | Date | Size | Files |
|---|---|---|---|
| 148.0.6Latest | February 13, 2026 | 152.6 MB | 64-bit MSIX |
Install from the command line
Silent install ›winget install --id Mozilla.Thunderbird.Beta.MSIX -eAdd-AppxPackage -Path "Thunderbird Setup 148.0b6.msix"Get-AppxPackage -Name MozillaThunderbird.MozillaThunderbirdBeta | Remove-AppxPackageRelated guide: How to use winget: install and update apps
Information
- Publisher
- Mozilla
- Category
- Chat & messaging
- Licence
- MPL-2.0
- Price
- Free
- Requires
- Windows 11 / 10 (Windows 10 1809+)
- Architecture
- 64-bit
- Installer
- MSIX
- Version
- 148.0.6
- Released
- February 13, 2026
- Added to the catalogue
- February 19, 2026
- Versions listed
- 1
- Website
- support.mozilla.org
- winget ID
- Mozilla.Thunderbird.Beta.MSIX
Ratings and reviews
No reviews yet. Be the first to rate it.
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Frequently asked questions
Is Mozilla Thunderbird Beta (MSIX) free?
Yes. Mozilla Thunderbird Beta (MSIX) is open-source software under the MPL-2.0 licence.
Is Mozilla Thunderbird Beta (MSIX) safe to download?
The download comes from archive.mozilla.org, which belongs to the publisher; ExeAtlas does not host or change the file. Compare its SHA256 hash with the one shown here, or open the VirusTotal report for that hash.
How do I install Mozilla Thunderbird Beta (MSIX) with winget?
Open PowerShell or Windows Terminal and run the winget command shown on this page. winget downloads the official installer and checks its SHA256 hash before running it.
Can Mozilla Thunderbird Beta (MSIX) be installed silently?
Yes. The silent install page lists the exact command for each installer.
Which Windows versions does Mozilla Thunderbird Beta (MSIX) support?
The installer requires Windows 10 1809 or newer and is available for 64-bit.
Does Mozilla Thunderbird Beta (MSIX) run on ARM (Windows on Arm)?
There is no ARM64 build; Windows 11 on Arm can run the 64-bit version through emulation.
What are alternatives to Mozilla Thunderbird Beta (MSIX)?
Signal, Discord, Telegram Desktop, Slack and Rocket.Chat. The alternatives page compares them.
