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Restore Firefox for Mac OS 10.11.6

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HELP!!! I tried upgrading my Firefox and stupidly has the new version replace my old one instead of keeping both versions. New version is not compatible with my operating system OS 10.11.6. Can you help me restore the version that will work on my Mac Pro? Is someone available to chat?

HELP!!! I tried upgrading my Firefox and stupidly has the new version replace my old one instead of keeping both versions. New version is not compatible with my operating system OS 10.11.6. Can you help me restore the version that will work on my Mac Pro? Is someone available to chat?

All Replies (1)

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Please see this -

Install firefox for Mac IOS 10.11.6 https://support.mozilla.org/mk/questions/1374946