Hi

It appears from your question that you are using Firefox Sync as a backup service. While it may be handy in some cases (such as transferring your data to a new device), we do not recommend relying on Sync for backup purposes.

If you have a copy of your Firefox profile for desktop Firefox, you should be able to recover your bookmarks and other data. To restore bookmarks, see this article. For instructions on recovering all of your data, see Restore bookmarks, passwords and data from an old Firefox profile.

If you have your data in Firefox on a mobile device, please follow these instructions to connect it to Sync and copy the data.

Be aware! Resetting your Mozilla account password without a recovery key will erase your data from Mozilla servers. Make sure to generate a recovery key in advance and safely store it.

Hope this will help you resolve your issue!

hanen_217, sometimes Windows will keepp some user data after a reset, depending on the options chosen. This might be in the (possibly hidden) directory "C:\Windows.old".

I am not familiar with the reset / reformat processes of other operating systems.

But if the data is not recoverable via Firefox Sync, then it might be worth checking whether the method that you used to reformat or reset your OS would have included a data backup?

(Yes that is probably a longshot as you used the term "reformat" rather than reset or refresh, but it is all I can think of.)