Found a bug Rated 4 out of 5 stars

Focus on left tab when closing active tab doesn't work when using multiple tab groups.

Other than that it's almost perfect with clever and intuitive logic. This is one of my top 5 essential addons and one of the few that I can't understand why Firefox doesn't have these features natively.

This review is for a previous version of the add-on (0.5.5.1-signed).