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

Migrating profiles from Time Machine backup, Firefox 70.X–Firefox 95

  • 1 reply
  • 1 has this problem
  • 8 views
  • Last reply by cor-el

more options

Hello, I am migrating profiles from a Time Machine backup of my mid-2012 Mac, which was running Yosemite, with Firefox 70-something, to my new M1 Mac, which is running Monterey, with Firefox 95.

I read an article which said I should copy ALL of the files inside my old profiles folder to the new folder and replace the new files. I did this, and my bookmarks and passwords showed up. However, now the type is about 1 pt. in size and everything within my window only reaches about half the width across.

I think what happened is that I copied over a file that deals with the size and display of text vs. resolution that was set for the old Mac.

My questions are: 1) What might the name of that profile file be? 2) Am I able to delete just that one file and things will display correctly? Or, 3) Do I need to do a re-install of version 95 and then only copy over bookmarks and password files?

Hello, I am migrating profiles from a Time Machine backup of my mid-2012 Mac, which was running Yosemite, with Firefox 70-something, to my new M1 Mac, which is running Monterey, with Firefox 95. I read an article which said I should copy ALL of the files inside my old profiles folder to the new folder and replace the new files. I did this, and my bookmarks and passwords showed up. However, now the type is about 1 pt. in size and everything within my window only reaches about half the width across. I think what happened is that I copied over a file that deals with the size and display of text vs. resolution that was set for the old Mac. My questions are: 1) What might the name of that profile file be? 2) Am I able to delete just that one file and things will display correctly? Or, 3) Do I need to do a re-install of version 95 and then only copy over bookmarks and password files?
Attached screenshots

All Replies (1)

more options

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.


  • 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)