TabSweeb by AnhTan_Dev

TabSweep is a tab management utility for Firefox.

It scans the tabs in the current browser window and identifies duplicate pages. Duplicate groups can be reviewed before closing, and TabSweep keeps important tabs such as the active tab, pinned tabs, and tabs playing audio protected.

The extension also groups open tabs by website so you can see which domains are using the most tabs.

TabSweep works entirely inside Firefox and does not require an account, external service, or remote server.