Main functionality is broken. When importing any cookie with expiration date, it will be set to a date 3 days from today instead.

This means after importing all cookies from a different browser you will be logged out from all websites in 3 days in Firefox. This defeats the purpose of importing cookies.

Had to debug the add-on and edit it in order to fix the problem.

Edit:
Developer says it was fixed but I won't be verifying the bugfix for now.