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Firefox for Mac

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Download Firefox 21.0

Firefox 21.0

  -  39.48 MB  -  Freeware

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 Firefox 21.0.


For those interested in downloading the most recent release of Firefox 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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  • Firefox 21.0 Screenshots

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

What's new in this version:

New:
- Enhanced three-state UI for Do Not Track (DNT).
- Firefox will suggest how to improve your application startup time if needed.
- Preliminary implementation of Firefox Health Report (see FAQ).

Changed:
- Ability to Restore removed thumbnails on New tab Page.
- Add-ons History API removals in Places.
- CSS -moz-user-select:none selection changed to improve compatibility with -webkit-user-select:none (bugs 816298).
- Graphics related performance improvements (bugs 809821).
- Removed E4X support from SpiderMonkey.

Developer:
- Implemented Remote Profiling.
- Integrated, Add-on SDK loader and API libraries into Firefox.

HTML5:
- Added support for <main> element.
- Implemented scoped stylesheets.

FixedL
- Some function keys may not work when pressed (833719).
- Browsing and Download history clearing needs unification to avoid confusion on clearing download history (847627).

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