Where does Firefox Tab Session Manager add on stores the sessions?

I have just reinstalled my firefox due to some performance issues.
I have installed the add on "Tab session Manager"
https://addons.mozilla.org/de/firefox/addon/tab-session-manager/?src=api
before and stored my current session in order to get it back, but It didn´t work as intended after reinstall.

What I have done:
I saved my profile folder.
Deinstalled firefox, runn ccleaner, run registry ccleaner, run windows defender virus scan and then run spybot search and destroy system check.

After I deleted all mozilla folders in the my profiles.
Then I Installed Firefox again.
I logged into my account to get back all my add ons
Then I imported passwords and bookmarks.

In order to restore my previous session, I have tried the following.

I opened
C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles\xxxxxx.default
and copied over from my profile save the following folder
sessionstore-backups

then I went into
C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles\xxxxxx.default\browser-extension-data
and copied over from my profile save the following folder
Tab-Session-Manager@sienori

Now when I open Firefox I am able to see my previously saved session from before the reinstall but when I click it, it just opens an empty firefox window.

Question: Does any one know where else there might be any files saved from this addon?

Solution 1:

Looks like it's under

C:\Users**Username**\AppData\Roaming\Mozilla\Firefox\Profiles**UserProfile** \browser-extension-data\Tab-Session-Manager@sienori

in a file called storage.js

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