Brilliant. Just brilliant. Rated 5 out of 5 stars

Fantastic addon! Just the thing I need to curb my ~60 tabs a day habit!

Can I suggest a fourth mode?

"Restrict: If the user tries to exceed the maxumum amount of opened windows/tabs, they will be presented with a simple message advising that they have reached the limit, and need to close off one or more windows/tabs to open any new ones."

I use a web based job tracking tool for work, and it's crucial that I submit changes to my open forms before closing them off. This would force me to go back and make sure that the forms were completed and updated, before being forced to close them, or start new tasks.