SingleTab

This is almost exactly what I needed, thank you! A couple of concerns that prevent me from giving it 5 stars, in order of most-to-least frustration: 1. For some reason it doesn't work on certain sites, such as my gmail inbox (https://mail.google.com/mail/u/0/#inbox) -- even though the URL is identical. I would really like it to work on Gmail in particular! ;) 2. I'd prefer if instead of closing the OLD tabs when I open a new one, it would instead close the NEW tab and jump over to the OLD one. This is because in some cases I have forms partly filled out or other incomplete work that I've forgotten about (hello, ADHD here). So then I end up losing that work. 3. It'd be nice to be able to configure which URLs it closes and which it ignores, perhaps using a regex, simple wildcard matching, or even a white/blacklist.

What a useful extension! Works perfectly and my browser is faster now that I don't have a lot of duplicate tabs open. Before, Chrome would slow down since I would forget to close out memory-hogging tabs; now it's much faster since forgotten tabs are closed when I go to the same site. The ability to temporarily disable the extension is also great, as is the fact that it counts the number of tabs closed so far (over 1000!).