After a few starting issues (whitelisted sites weren´t saved permanently, the migration didn´t work so I started with default sites on v10 @ Firefox 57) I had some mail exchange with the developer. He responded quite fast and had the right answers. He also implemented a feature request for the debug window within 1 or 2 hours which fixed my problems totally. Now I´m happy again, great work, 10 points go to Italy!