Description from extension meta
The best way to manage duplicate tabs.
Image from store
Description from store
Based on duplicate tabs closer. https://chromewebstore.google.com/detail/duplicate-tabs-closer-mon/hacblanmkniapibpnecicdcehogbnpob?hl=en-US
But better.
One new feature that users seek is the ability to delete all duplicate tabs on a per-group basis. Say for example you have five Google.com's open. There is now a button that deletes all but one, so it deletes four of them and leaves the latest one.
Also, weird height was fixed and overall looks much better.
https://github.com/jpfleischer/duplicate-tabs-closer/