Rated 4 out of 5 stars

Absolutely clean theme, I would like it to stand out a bit more from other dark themes.

Suggestion: Use more static blue color accents in the surface. Something to separate the List Area, Mail Content and Account-Overview-Tree for example :)

This review is for a previous version of the add-on (3.0). 

Hi, thanks for your feedback.
I will note the suggestions and see if I can impove it :).

Edit: Made an update, now it has a more blue accent color!