yes, free version. No, I only use firefox.Not sure about the question.
The cookies could have originated elsewhere and not necessarily "be Firefox".
Are you using free CCleaner?
More information and details needed.
No, I only use FF. There are websites that i visit, and no cookie is saved in Firefox .Ccleaner shows cookies from all web browsers, not just Firefox.
So you may have used a different web browser sometime in the past.