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Mozilla Thunderbird Eclipse ESR 140.4.0

Author: Mozilla
Date: 10/15/2025
Size: 67-131 MB
License: Open Source
Requires: 11|10|Linux|macOS
Downloads: 1197 times

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Introducing Mozilla Thunderbird Eclipse ESR

Mozilla Thunderbird Eclipse ESR is a versatile and free email application that stands out due to its ease of customization and a rich set of features that enhance user experience.

Eclipse ESR Versus Nebula ESR

128+ Nebula ESR: This version is part of the ESR 128 cycle, which started in July 2024 and will likely finish around September 2025.

140+ Eclipse ESR: This is the latest ESR release, which began in June 2025. It will be supported for about one year.

Since this channel for Mozilla Thunderbird Eclipse ESR is newer releases, it incorporates all the features and improvements that were introduced in Thunderbird releases up to version 140.

Some notable additions for this release ESR series include:

● Vertical tabs layout option
● You can unload tabs from memory without closing them
● It's easier to add custom search engines
● Tab grouping.
● Improved Reader View with more options for text and layout
● HTTPS-First mode
● Bounce Tracking Protection (in Strict ETP mode)
● HTTPS is now the default protocol shown in the address bar

You can view more change details here.

Speed, Safety, and all the Things You Need

This email client emphasizes safety, speed, and user-friendliness, making it an excellent choice for both individual users and organizations. Among its numerous built-in features are a straightforward message search, customizable views, and support for IMAP, POP, and RSS feeds.

The latest release of Mozilla Thunderbird Eclipse ESR includes a single dynamic toolbar that adjusts to display frequently used and contextually relevant options based on the currently active tab or workspace. You can further refine your experience by customizing the toolbar and window layout to align with your specific workflows. The graphical user interface (GUI) has also undergone a complete redesign over earlier versions, simplifying navigation and enhancing its visual appeal.

Thunderbird Eclipse ESR continues to support a wide range of Mozilla Add-Ons, enabling you to enhance the application's functionality and tailor it to your specific needs.

Geek Verdict

This email client is not only reliable but also prioritizes security, making it a solid choice for managing organizational emails. Key safety features include an efficient junk mail filter that analyzes incoming messages to detect potential spam. Users also have the ability to manually filter out any messages that the system might miss. Furthermore, Thunderbird employs robust security measures, including digital signing, message encryption, S/MIME support, certificate integration, and compatibility with security devices commonly used by enterprises and government agencies.

Looking for the portable version? We have it!

Similar:
● Mozilla Thunderbird Has Both Junk and Spam Folders

Version History for Mozilla Thunderbird Eclipse ESR:
https://www.thunderbird.net/en-US/thunderbird/140.4.0esr/releasenotes/

Screenshot for Mozilla Thunderbird Eclipse ESR

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