A superb add-on! I was using another Tree Tab add-on previously and came across this one - and it has just plenty of settings and possibilities to organize your work and your tabs. Now I'm able to easily group tabs to separate panels (Home/Work/Spouse) each having an isolated storage (container), which allows to be simultaneiously logged in to Google services with different accounts. There are plenty of customization settings, starting from custom icons and to fully customized behavior. I spent some time first to understand how to use all these, and still haven't explored all the possibilities, but I keep discovering still more and more convenient features (like reloading tab using long left click, or grouping tabs to a special Group tab, which shows an overview of all the contained tabs, or unloading a bunch of tabs to reduce memory usage). So couldn't help writing a review - and definitely recommend it!