Thunderbird 151 Is Here: What’s New in the Latest Release?

Mozilla has released Thunderbird 151, the latest version of the open source email client. This update brings several new features. Here’s what you need to know.

OAuth support for Thundermail and improvements for EWS accounts

In its blog post, Thunderbird highlights 3 main new features. The first is that Thunderbird 151 now supports OAuth for Thundermail, together with a new automatic account setup mechanism. This appears to refer to Thunderbird’s email service, but it’s hard to find much information about it (if you have any, I’m interested).

There is also something new on the Exchange Web Services (EWS) side. During setup, users can manually override the OAuth provider details, which gives them more control.

Thunderbird also mentions the ability to sort tasks by creation date or modification date, which was not possible until now.

Other improvements in Thunderbird 151

This release fixes bugs and also brings a few smaller new features, including:

• Default application: Thunderbird will once again check at startup whether it is set as the default mail application.
• OpenPGP: public keys are no longer automatically attached by default to messages that are only signed, preventing unnecessary attachments in unencrypted emails.
• Account Hub fixes: this release resolves Outlook account setup failures that occurred after password prompts following an OAuth sign-in. On the practical side, automatically detected values in Thunderbird are preserved if the user chooses to continue in manual mode.
• Search: Thunderbird 151 restores the result count display for the "Search in Message" feature.

This new version also fixes around twenty vulnerabilities, several of which are considered important. Unlike Mozilla Firefox, the Thunderbird email client does not appear to have been analyzed using the Claude Mythos AI. I’m saying that because many different people are credited for these various patched vulnerabilities.

Mozilla Thunderbird 151 is already available for direct download from the official thunderbird.net website. To learn more about this release, see this dedicated page.

Florian Burnel Co-founder of IT-Connect

Systems and network engineer, co-founder of IT-Connect and Microsoft MVP "Cloud and Datacenter Management". I'd like to share my experience and discoveries through my articles. I'm a generalist with a particular interest in Microsoft solutions and scripting. Enjoy your reading.

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