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SeaMonkey 2.20

  -  41.94 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 2.20.


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 2.20

  • SeaMonkey 2.20 Screenshots

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    SeaMonkey 2.20 Screenshot 1
  • SeaMonkey 2.20 Screenshot 2
  • SeaMonkey 2.20 Screenshot 3
  • SeaMonkey 2.20 Screenshot 4
  • SeaMonkey 2.20 Screenshot 5

What's new in this version:

SeaMonkey-specific changes:
- The Content Security Policy (CSP) 1.0 parser has been enabled.
- The Mixed Content Blocker has been enabled, blocking insecure active content loads on HTTPS pages.
- New mail alert information can be customized now (Preferences/Mail and Newsgroups/Notifications).
- A confirmation prompt has been introduced to protect against accidental permanent data loss when force-deleting messages using Shift+Del.
- MailNews Save As Template supports multiple selections now.
- The size on disk is now shown for newsgroup folders.

Mozilla platform changes:
- Added support for scrollbar style in OS X 10.7 and later.
- Enabled mixed content blocking to protects users from man-in-the-middle attacks and eavesdroppers on HTTPS pages (learn more).
- Improved about:memory's functional UI.
- Simplified interface for notifications of plugin installation.
- Enabled users to switch the search provider across the entire browser.
- CSP policies using the standard syntax and semantics will now be enforced.
- Implemented the HTML5 input type="range" form control.
- Added unprefixed requestAnimationFrame.
- Dropped blink effect from CSS rule text-decoration:blink and completely removed blink element.
- Fixed several stability issues.

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