Rated 2 out of 5 stars

This addon is wacked, any access key I use switches the tabs to a different group. does not do any search function.

This review is for a previous version of the add-on (0.31.3). 

Your reported issue with regard to tab group support has been fixed, insofar that selecting a tab now displays the correct group.
I was not able to reproduce the difficulties you experienced using Tabby2's search functionality.

The latest version can be found at: https://addons.mozilla.org/en-US/firefox/addon/tabby2/versions/