This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Cuireadh an snáithe seo sa chartlann. Cuir ceist nua má tá cabhair uait.

older browser

more options

have mac 10.10.5 -tried to install newer firefox browser (not compatible) and in process lost old version of broswer and all bookmarks. Can find and reinstall original browser and regain my bookmarks

have mac 10.10.5 -tried to install newer firefox browser (not compatible) and in process lost old version of broswer and all bookmarks. Can find and reinstall original browser and regain my bookmarks

Réiteach roghnaithe

Whoops, the last version of Firefox that runs on your MacOS is the Extended Support Release of Firefox 78. (See: Firefox Mac OS X 10.9, 10.10 and 10.11 users move to Extended Support Release)

You can download that from the archive server at:

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

This folder has the U.S. English version. If you prefer a different language/local, click the .. link above the file name and then click into the one you want.

This article has the steps to install from that .dmg file: How to download and install Firefox on Mac.

Can you get reconnected with your Firefox data?

Read this answer in context 👍 0

All Replies (1)

more options

Réiteach Roghnaithe

Whoops, the last version of Firefox that runs on your MacOS is the Extended Support Release of Firefox 78. (See: Firefox Mac OS X 10.9, 10.10 and 10.11 users move to Extended Support Release)

You can download that from the archive server at:

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

This folder has the U.S. English version. If you prefer a different language/local, click the .. link above the file name and then click into the one you want.

This article has the steps to install from that .dmg file: How to download and install Firefox on Mac.

Can you get reconnected with your Firefox data?