Hi! I'm sorry the last update has caused some trouble, I have put a small explanation in the add-on description.

The right click functionality has been improved in version 5.2.4 (although still not as smooth as in the Chrome version, as it is only just supported by Firefox).

Regarding the reset of the list: If you have an export of the list, you can import it again in version 5.2.4. If not, you can downgrade to version 2.0.1, to make an export first.