Unfortunately, as the warning says, resetting the Master Password removes logins and passwords from the Firefox storage. It's unlikely that you will be able to recover that information.

You need a backup copy of logins.json and key4.db in the profile folder.

You can look at a utility to browse System Restore points.

• https://www.nicbedford.co.uk/software/systemrestoreexplorer/
• https://www.shadowexplorer.com/

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.

• Help -> 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

Are you using Sync with your Firefox Account?
If so, DO NOT open Firefox on any other devices which are connected to that Firefox Account!

And let us know in this thread, so "we" can guide you further as to getting your logins data back on that computer thru Sync. But once another device connects to the Sync server, all hope is lost if Sync deletes the logins data on another device.

NO! Unfortunately not :( i am not using sync with my Firefox account. :/ Also, after the master password incident there's a notification about reconnecting with the account. But, as I have forgotten this one's password as well, I am unable to do so. :/ Btw, Won't I be able to recover the login info from Firefox profile as "cor-el" suggested? If I can't get the login info, i will have to do with the bookmarks only. :(