Duplicate Tab Closer от Simple Tasks

Pin this extension to your toolbar, then click the icon to close all duplicate tabs across all windows. This extension only closes tabs if the full URL is completely identical.

To close duplicate tabs across all non-private windows (including minimized ones), click the extension's icon on the toolbar of a non-private window.

To close duplicate tabs across all private windows (including minimized ones), click the extension's icon on the toolbar of a private window.

Data Collection:
Absolutely nothing.