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SeaMonkey 2.49.5

Web-browser, advanced e-mail, newsgroup and feed client, IRC chat, and HTML editing made simple—all your Internet needs in one application.

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SeaMonkey 2.49.5
Platform:
Language:
Language Version Windows
x64
Windows
x86
macOS
x64
Linux
x64
Linux
x86
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The SeaMonkey® Project

The SeaMonkey project is a community effort to develop the SeaMonkey Internet Application Suite (see below). Such a software suite was previously made popular by Netscape and Mozilla, and the SeaMonkey project continues to develop and deliver high-quality updates to this concept. Containing an Internet browser, email & newsgroup client with an included web feed reader, HTML editor, IRC chat and web development tools, SeaMonkey is sure to appeal to advanced users, web developers and corporate users.

Under the hood, SeaMonkey uses much of the same Mozilla Firefox source code which powers such products as Thunderbird. Legal backing is provided by the SeaMonkey Association (SeaMonkey e.V.).

Project News

September 4, 2019

SeaMonkey and the future

Wow! A new release and two news items together. What is cooking?

With the SeaMonkey 2.49.5 release the 2.49.x line comes to an end. Unless a catastrophic bug is discovered 2.49.5 will be the last ESR 52 based version. Backporting security fixes and at the same time working on the next, already overdue, major release is not possible with the few remaining developers.

Plans are to do further interim 2.53 versions based on a much enhanced Gecko 56 base while working on bringing you the next ESR 60 based 2.57 version. After 2.57 we will decide about the future. The current Mozilla Gecko codebase has seen a flow of constant major changes and api removals in the last 2 years and is no longer really usable for our needs. By the end of the year the SeaMonkey project is expected to be completely independent of Mozilla. We will see how this pans out but we are doing our best and already have a new infrastructure in place where we do builds and website hosting.

We would also like to remind everyone again that this a community project independent of Mozilla. So if you want to continue seeing future SeaMonkey releases please help by either donating money or even better help out with development. We are still committed and hope you are too.

September 4, 2019

SeaMonkey 2.49.5 released

The SeaMonkey project is proud to present SeaMonkey 2.49.5: The new release of the all-in-one Internet suite is available for download now! Based on Mozilla Firefox 52.9 ESR and further enhanced, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.49.5 is available in 20 languages, for Windows, MacOS x64 and Linux.

Automatic upgrades from previous versions are, for most configurations, disabled for this release. If you need to upgrade from an earlier version, please download the full installer from the downloads section and install SeaMonkey 2.49.5 manually over the previous version.

This release adds officially supported Windows x64 and Linux x64 versions. If you want to install the Windows x64 version please download the full installer and uninstall the old x86 release first. Your profile data will be kept during an uninstall. Support for the macOS x86 unified binary is dropped because of using a more current macOS development environment.

For a more complete list of major changes in SeaMonkey 2.49.5, see the What's New in SeaMonkey 2.49.5 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

April 3, 2019

Help squashing bugs in mail and news

Our Thunderbird friends ask for help squashing bugs. If you have some spare time help them and also us because SeaMonkey and Thunderbird use a shared codebase for mail and news.

Some Details from the announcement:

We are grateful to have a very active set of users who generate a lot of bug reports and we are requesting your help in sorting them, an activity called bug triage. We’re holding “Bug Days” on (all day, EU and US timezones) and (EU and US timezones until 4pm EDT). During these bug days we will log on and work as a community to triage as many bugs as possible. With several of us working at the same time we can help each other in real time – answering questions, sharing ideas ideas, and enjoying being with like-minded people.

No coding or special skills are required, and you don’t need to be an expert or long term user of Thunderbird. Some things you’ll be doing if you participate:

But we hope you’ll join us on the 8th or the 13th via #tb-qa on Mozilla’s IRC so that we can put these bugs in their place which helps make Thunderbird even better. If you have any questions feel free to email Ryan.

Visit the Thunderbird Blog to see the full announcement.

February 14, 2019

Today is "I love Free Software Day"

And if you are wondering when the next release will be out, then read about the progress we are making in our SeaMonkey Project Blog.

July 27, 2018

SeaMonkey 2.49.4 released

The SeaMonkey project is proud to present SeaMonkey 2.49.4: The new release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 52.9 ESR, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.49.4 is available in 20 languages, for Windows, Mac OS X and Linux.

For a more complete list of major changes in SeaMonkey 2.49.4, see the What's New in SeaMonkey 2.49.4 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

May 4, 2018

SeaMonkey 2.49.3 released

The SeaMonkey project is proud to present SeaMonkey 2.49.3: The new release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 52.7.3 ESR, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.49.3 is available in 20 languages, for Windows, Mac OS X and Linux.

For a more complete list of major changes in SeaMonkey 2.49.3, see the What's New in SeaMonkey 2.49.3 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

February 15, 2018

SeaMonkey 2.49.2 released

The SeaMonkey project is proud to present SeaMonkey 2.49.2: The new release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 52.6 ESR, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.49.2 is available in 20 languages, for Windows, Mac OS X and Linux.

For a more complete list of major changes in SeaMonkey 2.49.2, see the What's New in SeaMonkey 2.49.2 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

November 6, 2017

SeaMonkey 2.49.1 download problem solved

We fixed the earlier problem with downloads from the offical server not working. Unfortunately we are still unable to enable updates for most configurations. If you are not prompted for an update please download the full installer from here.

November 4, 2017

SeaMonkey 2.49.1 released

The SeaMonkey project is proud to present SeaMonkey 2.49.1: The new major release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 52.4 ESR, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.49.1 is available in 20 languages, for Windows, Mac OS X and Linux.

For a more complete list of major changes in SeaMonkey 2.49.1, see the What's New in SeaMonkey 2.49.1 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

August 13, 2017

Download problems with NoScript active

If you are using NoScript you might encounter a certificate error when trying to download SeaMonkey from this site. NoScript tries to force an https connection for an http only site. It is not a NoScript problem but how the Mozilla server, from which downloads are delivered, is configured.

In this case please add download.cdn.mozilla.net to the NoScript "Never force secure (HTTPS) connections" options or turn off NoScript for this download only. The settings are located in the NoScript options under "Advanced->HTTPS".

July 31, 2017

SeaMonkey 2.48 released

The SeaMonkey project is proud to present SeaMonkey 2.48: The new major release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 51, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.48 is available in 19 languages, for Windows, Mac OS X and Linux.

Automatic upgrades from previous versions are, for most configurations, disabled for this release. If you need to upgrade from an earlier version, please download the full installer from the downloads section and install SeaMonkey 2.48 manually over the previous version.

For a more complete list of major changes in SeaMonkey 2.48, see the What's New in SeaMonkey 2.48 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

July 12, 2017

Fight for Net Neutrality

The SeaMonkey project supports the battle for the net campaign. If you live in the US please do it too. But companies in other countries are also lobbying for the same goal so even if you are not a US citizen keep an eye open.

April 15, 2017

SeaMonkey 2.48 Beta 1 released

The SeaMonkey project is proud to present SeaMonkey 2.48 Beta 1: The new Beta release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 51, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.48 Beta 1 is available in 18 languages, for Windows, Mac OS X and Linux.

This is a Beta Release. We encourage testers to get involved in discussing and reporting problems as well as further improving the product.

For a more complete list of major changes in SeaMonkey 2.48 Beta 1, see the What's New in SeaMonkey 2.48 Beta 1 section of the Release Notes, which also contains a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

December 22, 2016

SeaMonkey 2.46 released

The SeaMonkey project is proud to present SeaMonkey 2.46: The new major release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as Firefox 49, it delivers those same developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

SeaMonkey 2.46 is available in 26 languages, for Windows, Mac OS X and Linux.

For a more complete list of major changes in SeaMonkey 2.46, see the What's New in SeaMonkey 2.46 section of the Release Notes, which also contain a list of known issues and answers to frequently asked questions. For a more general overview of the SeaMonkey project (and screen shots!), visit www.seamonkey-project.org.

March 14, 2016

SeaMonkey 2.40 released

The SeaMonkey project is proud to present SeaMonkey 2.40: The new major release of the all-in-one Internet suite is available for download now! Building on the same Mozilla platform as the newest Firefox release, it delivers the latest developments in web technologies such as HTML5, hardware acceleration and improved JavaScript speed.

The Release Notes feature more in-depth lists of the improvements and known issues with the new version as well as installation requirements, instructions, and answers to frequently asked questions.

Full article...

The SeaMonkey Internet Application Suite

SeaMonkey has inherited the successful all-in-one concept of the original Netscape Communicator and continues that product line based on the modern, cross-platform architecture provided by the Mozilla project.