January 1, 2009
TabCloser: Close all “example.com” tabs
With TabCloser, you can close all tabs of a specific domain in just 2 clicks. After installing the Firefox add-on, there will be a ““Close all example.com tabs” option when you right-click on a tab.

With Widexplorer, you can load up several websites simultaneously in a single window/tab, and have them arranged side by side. I have not seen any useful iframe usage for quite some time already, but Widexplorer looks promising to certain users.
Firefox by default is already very powerful internet browser, but you are probably not getting the most out of it. Getting the most out of Firefox basically means doing more on Firefox with less time. That will definitely increase your productivity.