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Firefox downgrade

rvargas1325
rvargas1325
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I accidentally updated my Firefox and cannot open it now. I am on a Mac operating system 10.10.5. And I can't upgrade my OS because of work. What version of Firefox do I need?

I accidentally updated my Firefox and cannot open it now. I am on a Mac operating system 10.10.5. And I can't upgrade my OS because of work. What version of Firefox do I need?

All Replies (2)

jonzn4SUSE
jonzn4SUSE
  • Top 10 Contributor
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Here ya go.

https://support.mozilla.org/en-US/kb/firefox-mac-osx-users-esr#firefox:mac:fx91&firefox-enterprise:linux:

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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I think actually you might need the previous one (78 instead of 91):

https://archive.mozilla.org/pub/firefox/releases/78.15.0esr/mac/en-US/

If you want a language-locale other than U.S. English, click the .. link on that page and then click into the desired locale.

Once you have the .dmg file, the installation steps are the same as this support article: How to download and install Firefox on Mac.