Handy and efficient Rated 4 out of 5 stars
In general, this is a neat little addon that's always handy, especially if you're keeping FF running for days, like me.
A few comments:
1. It would be more helpful to wait for the user's confirmation before actually closing the tab. For example, you might have written something in one of the tab's text area... closing that tab would be inconvenient to say the least.
2. In case you do go in the direction of the latter, it also be possible to offer a closure of tabs with the same domain, not necessarily the exact URL.
3. Accessibility: remembering going to Tools->Close Repeated tabs, or remembering the hotkey is almost a drag as closing the repeated tabs manually. Could be a good idea to add an action button on FF lower bar.
4. Compatibility: tested with the following applications:Multiple Tab Handler, FoxTab, Tab Mix Plus, Tab Scope, SiteLauncher, and New tab King and found no colossions :-)