Additional two great extensions for Firefox januari 2, 2006 Johan KänngårdComments are off for this post. FLST is an extension, to be used in Mozilla Firefox. This one makes sure that the tab you selected last is selected when you close a tab. It can also be used to cycle through all tabs as a slideshow. Duplicate Tab adds a context menu item when right clicking on a tab, that lets you duplicate a tab with its history etc.