Shortcut in Firefox to switch tabs is Ctrl+Tab. However, that directly takes you to your selected tab, without showing a preview of it first. This is unlike the Alt+Tab functionality of Windows that shows you preview of programs, before switching to them.
Ctrl-Tab is a free plugin for Firefox to replace Ctrl+Tab functionality of Firefox. After installing this plugin, when you do Ctrl+Tab in Firefox, you get a preview of tabs, and you can navigate through them, before selecting the tab that you want to switch to.
Interesting thing about Ctrl+Tab is that it presents tabs in most recently used order, instead of the order in which they are laid out. This again matches the Alt+Tab behavior of Windows.
Firefox lets you close a tab by pressing Ctrl+W (as we detailed here). Ctrl+Tab plugin lets you close a tab while you are previewing it. Just go to that tab in preview mode, and press W while holding Ctrl to close a tab in Firefox.
Another great feature of Ctrl+Tab is that you can see all Firefox tabs together in a grid view. Just press Shift + Ctrl + Tab, and all the tabs will be presented in a grid layout. You can select any tab to open, or close.
Ctrl+Tab is a must have plugin for Firefox if you tend to open too many tabs at same time.
