Rated 1 out of 5 stars

It's nice, this try to give us the extra-columns back.

But first, it is an add-on only, I miss this feature as built-in feature, and I'm not able to understand why this feature has been tossed away by the Thunderbird developers.

Secondly, this add-on doeas not bring back the main function of this feature: to show the summary for closed folders. You always have to open all folders of a tree to know how much mail are stored there.

This review is for a previous version of the add-on (0.3).