Rated 4 out of 5 stars
As a long time user of this excellent add-on I have only high praise for this. However, with Thunderbird 3.x the icon is too large to fit the header pane, touching its bottom edge. That doesn't look professional and is quite hard on the eye, when you spend many hours a day looking at Thunderbird interface.
I know that the icons are submitted at a fixed dimension (48x48), so there is only few options:
a) scale the icons down
b) create a new catalog of icons altogether, prompting users to submit smaller size (crazy idea, I admit)
c) move the oversized icon to some other place in the header pane (to the far right, after the buttons?)
Hopefully the developer would come up with some clever idea to polish this annoyance. Otherwise, keep up the good work!