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Preview of Unclone — Duplicate Tab Manager

Unclone — Duplicate Tab Manager by dclabs

Find and close duplicate tabs — but you decide what "duplicate" means, and which copy stays. Compare by authority, path or query, see exactly what's being matched, and undo anything. No tracking, no network requests.

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A group of duplicates: the pinned tab is kept, another copy has been spared by hand, and the third is ready to closeThe level explanation and the live preview over a real URL, with the tracking parameter struck throughThe history of what was closed, with the time and whether it was manual or automaticThe same case in dark modeSettings
About this extension
You have the same page open four times. Again.

It happens to everyone: you open a link, forget about it, open it again, and by Thursday your tab bar is a row of identical favicons.

Unclone finds those copies and closes them. What makes it different is that it asks you what "the same page" means instead of deciding for you.

Three levels, and you pick

They're named after the parts of a URL, because that's exactly what they are:
  • Authority — the same site. Every page on it counts as one. Good for a research binge that got out of hand.
  • Path — the same page, whatever comes after the ?. This is the default, and it's right most of the time.
  • Query — the same page with exactly the same parameters. Because ?page=2 really is a different page.

It shows its work

Press the ⓘ and Unclone highlights, on your current tab's real address, which part it's comparing and which part it's ignoring.

Tracking junk like utm_source and fbclid never changes the page you get, so it's ignored at every level — and shown struck through, so you can see why two addresses that looked different were treated as twins.

You decide which copy survives

Unclone proposes one and never insists. Swap it, or tick as many as you want to keep. When two long URLs differ only at the very end, it hides the part they share and shows you the part they don't, so you're not hunting for the difference across 200 characters.

Nothing gets lost
  • Every close can be undone, browsing history and all.
  • Pinned tabs stay. The tab you're looking at stays.
  • Tabs in different containers are never twins.
  • A local log of what was closed and when.
  • Automatic mode exists, and it's off until you say otherwise.

Also in the box

Group what's left by site using Firefox's native tab groups (138+), reversible down to each tab's exact original position. Light and dark themes. Keyboard shortcuts. English and Spanish.

The boring part that matters

No network requests. None. No analytics, no telemetry, no remote code. It can't read the content of any page — only the address and title of your tabs, which is what comparing them takes.

Your settings and the optional history live on your device and stay there. The code ships unminified, with no build step and no dependencies, so what you can read is what runs.
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Permissions and data

Required permissions:

  • Access recently closed tabs
  • Access browser tabs

Optional permissions:

  • Display notifications to you

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
  • Copy add-on ID
Version
1.2.1
Size
141.74 KB
Last updated
7 days ago (Sep 15, 2026)
Related Categories
  • Tabs
License
Mozilla Public License 2.0
Privacy Policy
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Version History
  • See all versions
Tags
  • container
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