Rated 4 out of 5 stars

Sadly the menu is completely in German, please translate it to English or Dutch.
Update: Thanks for the reply, now I can figure out the options menu (I gave you a star extra).

This review is for a previous version of the add-on (4.6.1-signed). 

Thanks for telling me that. It seems that if your Firefox is set to Dutch, it uses "de" locale if "nl" is not present. Fixed in the next version by renaming "de" to "de-DE".