Hope that logically not possible. Because firefox allows to restore the most recent session.

Isn't there some code or accessing hard-drive somehow to retrieve?

No. There is no such possibility. However you can manually save sessions using a firefox addon called Save Session. And restore the saved sessions.

Click here to installSave Session Addon

Hope this helps you.!

I'm sure there must be a way. You probably just don't know it. No offense. Thanks for your assistance

Firefox only keeps the session data of the previous session. Firefox does create a backup (upgrade.js-<build_id>) when you update Firefox.

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

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

You can copy a file from the sessionstore-backups folder to the main profile and rename the file to sessionstore.js to replace the current file (make a backup copy of the current sessionstore.js).

See also:

• http://www.ghacks.net/2014/06/27/mozilla-launches-improved-session-restore-firefox-33/