Rated 4 out of 5 stars

This understated theme is a hidden gem amongst a lot of clutter. The designer obviously knows what he is doing, and as far as I am concerned this is among the very best themes ever created for Thunderbird.

But unfortunately it has one very serious drawback, at least on this laptop’s mainstream, default-set, graphics display. The contrast between highlighted message headers and non-highlighted message headers in the message pane (or the message tree for that matter) is so minimal as to be indescernible, so if, for example, you wanted to delete five consecutive messages at once, you’d be taking a great risk because you can't really recognize what you've highlighted. This is a dealbreaker kind of error, so please fix this!

Otherwise, a terrific piece of work.