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  • Last reply by James

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Edit a Question

Edit a Question
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Modified by reednikki

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I guess you figured out Firefox 78.15.0 ESR was the last version for macOS 10.11

Below is what I was going to post before you edited.

Firefox since Fx 79.0 and later including the current Fx 100 and Fx 91 ESR requires Mac OS X 10.12 (ten.twelve) at minimum.

Besides updating your OS to Mac OS X 10.12 (ten.twelve) or later, the most current Firefox version you can install on mac OS 10.11.6 is Fx 78.15.0 ESR though it is EOL with no more updates.

In case you ever need the Firefox 78.15.0esr file. other locales at