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SeaMonkey 2.39

  -  79.34 MB  -  Open Source
Free Download

Security Status

Sometimes latest versions of the software can cause issues when installed on older devices or devices running an older version of the operating system.

Software makers usually fix these issues but it can take them some time. What you can do in the meantime is to download and install an older version of SeaMonkey 2.39.


For those interested in downloading the most recent release of SeaMonkey for Mac or reading our review, simply click here.


All old versions distributed on our website are completely virus-free and available for download at no cost.


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If you have any questions or ideas that you want to share with us - head over to our Contact page and let us know. We value your feedback!

Download SeaMonkey 2.39

  • SeaMonkey 2.39 Screenshots

    The images below have been resized. Click on them to view the screenshots in full size.

    SeaMonkey 2.39 Screenshot 1
  • SeaMonkey 2.39 Screenshot 2
  • SeaMonkey 2.39 Screenshot 3
  • SeaMonkey 2.39 Screenshot 4
  • SeaMonkey 2.39 Screenshot 5

What's new in this version:

Extensions (Add-ons) and Themes:
- Extensions installed under SeaMonkey 1.x are not migrated to SeaMonkey 2, and may not be compatible for reinstalling in this version due to major changes in our architecture. Please report any issues to the maintainer of the extension. Extensions and Themes for SeaMonkey 2.39 can be installed from the SeaMonkey Add-Ons website or the "Get Add-Ons" section in the Add-ons Manager
- Extensions with binary components such as Lightning, Enigmail and HTML Validator only work on certain platforms (e.g. Windows). Furthermore they need to be adjusted for each new SeaMonkey release, which also means that an old version of such an add-on can break SeaMonkey if you disabled compatibility checking (which e.g. happens when you install the Add-on Compatibility Reporter add-on)
- For Lightning, please check the Stable Releases section on the Calendar Versions page. Alternatively check the Lightning add-on page (Development Channel at the bottom of the page)
- For Enigmail, please refer to the Enigmail Nightly Builds page
- For HTML Validator you need to check whether the Firefox version that appears on SeaMonkey's about: page is listed on the 0.9x download page. Note that only Windows is supported at this time
- SeaMonkey 2.29 dropped support for the legacy JavaScript Debugger interface (JSD1). Hence add-ons that relied on it, like the JavaScript Debugger (Venkman) that came bundled with SeaMonkey, or Firebug 1.x, have stopped working. While Venkman has been discontinued, Firebug can simply be upgraded to a more recent version (2.x) which supports the new JSD2 interface. If you are searching for a Venkman replacement (especially for debugging SeaMonkey itself or add-ons), have a look at the Tiny JavaScript Debugger add-on

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