does not work, but there are alternative Rated 1 out of 5 stars
This addon does not work for me. It did`n sorts not loaded tabs and as others have said no sort options.
Here is an alternative - sort_tabs-2.100910.18-fx+sm-win.xpi http://releases.mozilla.org/pub/mozilla.org/addons/5372/ .
I do not know why this addon and page it developer disappeared from the site, but the addon kept on the server.