Are you talking about the browser, or sync?

Do you know how the data was lost?

Just to be sure; Type about:preferences#security<enter> in the address box. Look under Logins,

Note: For Firefox v56+ its; about:preferences#privacy Look under Forms & Passwords Or type about:logins<enter> in the address box. +++++++++++++++++++++++++++++++ Turn on Remember Logins. To check the passwords you have listed, press Saved Logins.

Press the Exceptions button and see what's inside.

https://support.mozilla.org/en-US/kb/password-manager-remember-delete-edit-logins

If the above does not help; Firefox 80+ has a logins-backup.json file in the profile folder that can be used in case of issues with logins.json or to undo an accidental delete of a login, so you can check if you can find this file in the profile folder or in a backup and replace the current logins.json. Make sure to keep a backup copy of all involved files (logins.json and key4.db and logins-backup.json)

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.

Help -> More Troubleshooting Information -> Profile Folder/Directory: Windows: Open Folder; Linux: Open Directory; Mac: Show in Finder https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data

If you use a Primary Password then you can prevent losing passwords by canceling the PP prompt. You need to logout beforehand by canceling a PP prompt, e.g. by clicking the eye icon in Lockwise (about:logins).

Also see; https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update

You didn't change the password for the Sync account as that whould have wiped all data stored on the Sync server ?

If you use the Time Machine or other backup then try to restore file(s) from this backup.

• https://support.apple.com/guide/mac-help/restore-files-mh11422/mac

Location used for the main profile that keeps your personal data (Root Directory on about:profiles).

• ~/Library/Application Support/Firefox/Profiles/<profile>

Hello! Thank you for all the replies. Really helpful.

What happened was I updated my OS and deleted files in the application support folder. I was wondering if there's a onilne copy of my Firefox account.

I also noticed in my account that I'm still logged in in the previous name of my macbook.

Thank you so much!

Hi Johnpaolo, Yes, your Firefox user data is kept within the Application Support folder, so deleting that folder would have deleted your locally stored passwords (and other user data). Were you using the Firefox Sync feature? If so, just sign in to your account and everything will be synced from the server, including passwords.

Hi, Chris!

I was signed in before I updated my OS. Maybe I was not using Firefox Sync which is why when I signed in again, my passwords did not appear. I shouldn't have deleted my files in the application support folder. :(

Do you have a Time Machine back up?

I don't. :(

You can install the About Sync extension in Firefox 72 and newer on desktop to check what data is stored on the Sync server via the about:sync page provided by this extension.

• About Sync https://addons.mozilla.org/firefox/addon/about-sync/

Close and restart Firefox to access the about:sync page added by this extension (see the about:about page for possible about pages).

Thank you everyone for all the help! I learned a lot and will be more careful next time by backing up Application Support files and syncing regularly.

Back up and restore information in Firefox profiles {web link} I use a Legacy add-on that makes backups of my user profile, Just In Case. Unfortunately, it is not compatible with the current Firefox.

Every now and then, open the profile folder and create a copy of the current profile as is to another location on your hard drive. This way you will have a backup.

If you do this each day, you will not lose much data. This should be done with Firefox Closed.

Note: In case you need to restore from these backups, you may need to overwrite old or corrupted files.

Thank you for this! I'll do this next time.

What is interesting is that I lost nothing in my bookmarks.

Again, thank you!

In Firefox, different information/data is stored in different files.