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

Bookmarks and Passwords from deleted profile

more options

My CPU usage suddenly began topping out when I would launch a Firefox session. I followed advice on-line to remedy the problem and created a new profile then deleted the old profile. As described in the on-line process I was following, when deleting the profile the option came up: "delete files and profile" or "just delete profile". I selected "just delete profile". How can I link the files from the deleted profile to the new one? Also, deleting the profile didn't improve the excessive CPU usage. I'm not very technical.

Thanks for any guidance on either or both issues. RF

My CPU usage suddenly began topping out when I would launch a Firefox session. I followed advice on-line to remedy the problem and created a new profile then deleted the old profile. As described in the on-line process I was following, when deleting the profile the option came up: "delete files and profile" or "just delete profile". I selected "just delete profile". How can I link the files from the deleted profile to the new one? Also, deleting the profile didn't improve the excessive CPU usage. I'm not very technical. Thanks for any guidance on either or both issues. RF

Chosen solution

If you want to return to the old profile then you can use the Profile Manager to create a new profile and use "Choose Folder" to select the deleted profile.


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)

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

Read this answer in context 👍 0

All Replies (2)

more options

Chosen Solution

If you want to return to the old profile then you can use the Profile Manager to create a new profile and use "Choose Folder" to select the deleted profile.


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)

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

more options

Thanks cor-el. I used Profile Manager and created another new profile. When selecting the directory, the profile directory of the profile I deleted was available as an option. Worked perfectly.