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SeaMonkey for Mac

SeaMonkey 2.21

  -  46.2 MB  -  Open Source

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 2.21.


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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  • SeaMonkey 2.21 Screenshots

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

    SeaMonkey 2.21 Screenshot 1
  • SeaMonkey 2.21 Screenshot 2
  • SeaMonkey 2.21 Screenshot 3
  • SeaMonkey 2.21 Screenshot 4
  • SeaMonkey 2.21 Screenshot 5

What's new in this version:

SeaMonkey-specific changes:
- Implemented an option to thread messages received by date.
- Allowed deletion of news posts by default.
- Implemented optional taskbar preview-per-tab.
- Added support (permission prompt) for desktop notifications.
- Added Isn't operator for searching by Priority.

Mozilla platform changes:
- Support for new scrollbar style on OS X 10.7 and newer.
- Accessibility related improvements on using pinned tabs (bug 577727).
- Major SVG rendering improvements around Image tiling and scaling (bug 600207).
- Removed support for sherlock files that are loaded from application or profile directory.
- Support for W3C touch events disabled (bug 888304).
- Fixed several stability issues.