Check these replies:

https://support.mozilla.org/en-US/questions/982636 https://support.mozilla.org/mk/questions/1064227

I need to transfer cookies - and ONLY cookies - from one Firefox profile to another. Copying the cookies.sqlite file did not work - none of my preferences or logins were saved on the new profile. How can I copy all my cookies to a new profile?

Cookies, preferences, are logins are all stored in different files. Do you need to transfer preferences and logins?

Recovering important data from an old profile

I would advise against copying prefs.js to transfer preferences as this file contains a lot of profile/platform specific data. Best is to redo changes in the new profile via "Settings".

• https://support.mozilla.org/en-US/kb/firefox-options-preferences-and-settings

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)

Cookies, preferences, are logins are all stored in different files. Do you need to transfer preferences and logins?

Yes. It's only my cookies that don't transfer. I have tried everything on multiple different new profiles, but it's ONLY the cookies.sqlite file that does nothing. None of my logins or preferences on any website are saved. The file does move properly - it's even the exact same file size in both folders. For some reason, though, Firefox just ignores this cookies.sqlite file and I end up with no cookies, despite moving the file.

Note that cookies from open tabs are stored in sessionstore.jsonlz4 as part of session data and websites may use other ways to validate session ID cookies.

Note that cookies from open tabs are stored in sessionstore.jsonlz4 as part of session data and websites may use other ways to validate session ID cookies.

I can't find this file in my profile folder - only sessionstore-backups. Where is it?

sessionstore.jsonlz4 is only present when Firefox is closed.

When Firefox is running then the files in the sessionstore-backups folder are used.

You will normally find these files in the sessionstore-backups folder:

• previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
• recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
• recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
• upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)

sessionstore.jsonlz4 is only present when Firefox is closed. When Firefox is running then the files in the sessionstore-backups folder are used. You will normally find these files in the sessionstore-backups folder:

• previous.jsonlz4 (cleanBackup: copy of sessionstore.jsonlz4 from previous session that was loaded successfully)
• recovery.jsonlz4 (latest version of sessionstore.jsonlz4 written during runtime)
• recovery.baklz4 (previous version of sessionstore.jsonlz4 written during runtime)
• upgrade.jsonlz4-<build_id> (backup created during an upgrade of Firefox)

I tried moving some files around, nothing.

However, I did manage to find out how to view my cookies. The cookies are the same for both profiles but still I have the same issue of no preferences or logins on any website being transferred!

The browser cookies from main user account cannot be transferred to other user account. However you can transfer favorites and bookmarks of one user account to another user account by exporting them to a file and importing it in another user account.

Regards, Will