At home I run Firefox 16.0.2, at work I run version 17.0.1. I am a Senior Software Engineer, so I know how-to write code, debug, etc. In both versions of Firefox I am running, I tried using this plugin, however it caused clicking on tabs to have NO affect, it would stay on the tab that was loaded. Even CTRL-TAB wouldn't' do anything. Now it did highlight the selected tab, but the window that shows the content doesn't change, or refresh.
Example, I was on Google, and had a CNN tab open. I click on my CNN tab, it becomes highlighted, I see CNN in the address bar, but I am still looking at Google search. CTRL-TAB (tab switching) or CTRL-SHIFT-TAB (switch backwards) has the same affect.
Disabling this plugin fixed this issue.
Seems like a VERY good plugin, unfortunately, there is some compatibility issues.