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Firefox for Mac

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Download Firefox 66.0

Firefox 66.0

  -  64.9 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 66.0.

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 66.0 Screenshots

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What's new in this version:

- Firefox now prevents websites from automatically playing sound. You can add individual sites to an exceptions list or turn blocking off. To learn more about block autoplay, which will be rolled out gradually to all users, visit the Mozilla blog
- Improved search experience
- Improved performance and better user experience for extensions: find a specific webpage faster when you have a lot of tabs open: You can now search within all of your open tabs from the tab overflow menu, easier search via a redesigned new tab in Private Windows
- Extensions now store their settings in a Firefox database, rather than individual JSON files, making every site you visit faster
- A redesigned keyboard shortcuts section in about:addons makes it easier to view and adjust default shortcuts
- Redesigned certificate error pages help you better understand and resolve issues, including identification of certificate issuers for anti-virus software
- Added basic support for macOS Touch Bar
- Experimenting with an improved Pocket experience in New Tab with different layouts and more topical content
- Improved performance and reduced crash rates by doubling web content loading processes from 4 to 8
- Easier, passwordless security: Added support for Windows Hello on Windows 10, allowing you to use your face, fingerprint, or external security keys for website authentication
- Enabled AV1 support on 32-bit Windows and MacOS. Firefox now supports the next-generation, royalty-free video compression technology called AV1.Read about Mozilla’s contribution to this new open standard.

- The Dark and Light Firefox themes now override the system setting for title bar accent color on Windows 10
- Linux users: Resolved an issue that caused Firefox to freeze when downloading files
- Various security fixes

- System title bar is hidden by default to match Gnome guideline for Linux users

- DevTools Inspector is now fully usable when the Debugger is paused
- Lowered priority of setTimeout and setInterval during page load to improve overall page load performance

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