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firefox on new apple operating systems

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  • Last reply by cor-el

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I am wanting to upgrade my old mac mini to the new version with the M01 chip. Can I bring Firefox and all my extensions to Big Sur on Apple?

I am wanting to upgrade my old mac mini to the new version with the M01 chip. Can I bring Firefox and all my extensions to Big Sur on Apple?

All Replies (2)

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unfortunately, the widevine extension on FF will 100% not work on mac's.

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You can possibly use Sync to transfer your add-ons and some other personal data.

Alternatively you can transfer data directly using a removable UBS drive.

You can copy certain files with Firefox closed to the current profile folder to transfer or recover personal data. Note that best is to avoid copying a full profile folder.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.


  • bookmarks and history: places.sqlite
  • favicons: favicons.sqlite
  • bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
  • cookies.sqlite for the Cookies
  • formhistory.sqlite for saved autocomplete Form Data
  • logins.json (encrypted logins;32+) and key4.db (decryption key;58+) for Passwords saved in the Password Manager
    key3.db support ended in 73+; to use key3.db in 58-72, make sure to remove key4.db
  • cert9.db (58+) for (intermediate) certificates stored in the Certificate Manager
  • persdict.dat for words added to the spell checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
  • sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)