This disables tabbed browsing features of Firefox completely. I was inspired from the the anti-tabbed browsing project. So, this is for users which want Firefox to be an SDI application.
The feature "History" -> "Recently Closed Tabs" becomes "Recently Closed Windows". You can reopen closed windows from the menu.
If you wish to enhance tabbed browsing features, I recommend you to try the Tabbrowser Extensions.
If you see any problem, see FAQ at first. If there is no solution, post a report to the issue tracker on the GitHub please.
If you use Mozilla Suite or Netscape 7, see How to install and update? (contains important notes) This extension includes a self uninstaller. Please open the preferences panel Preferences > Advanced > Tab Killer, click the button Uninstall in the dialog. When you couldn't remove it completely, see How to uninstall by hand?
Released version includes following language packs: