TabFind od Slezak

This addon is used to list tabs, switch to a tab, delete tabs, find duplicate tabs, and search for tabs.

ALL: Lists all the tabs you have open. Clicking on a tab switches to that tab and clicking the x will close the tab. Search box will filter the tab list. Only searches in the tab names.
DUPLICATES: Lists the tabs you have open with identical names. Clicking on a tab switches to that tab and clicking the x will close the tab. Clear Duplicates button will remove the extra tabs leaving you with the most recent copy from the duplicates.

Also displays the number of tabs you have open in the current window and all windows, and the number of windows open.