It has been a long time since I have taken a look at Tab Mix Plus. I know a lot of people who use it, and it continues to be one of the most popular Firefox add-ons out there. So the first question to ask is, what makes it so darn special?
Well, the main goal of Tab Mix Plus is to give Firefox’s tabs more capabilities. You can quickly duplicate tabs, control the tab focus, you get all kinds of tab clicking options, undo tabs and windows, and that is just scratching the surface.
It also includes a full-featured session manager with crash recovery that can save and restore combinations of opened tabs and windows.
Need help using one Tab Mix Plus’s features? They have a handy set of user forums here:
All in all, Tab Mix Plus is still a great addition to the Firefox browser if you need to do “more” with your tabs than the default Firefox install or any other add-ons give you.

Want a new way to quickly and elegantly switch between tabs in Firefox? 
The events you can assign an action to are:
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We have colored them, moved them, shrunk them – so why not add little colored flags to your tabs? The
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