What does Close New Duplicate Tabs do?

Close New Duplicate Tabs focuses on preventing newly opened duplicate browser tabs from cluttering Firefox. It is catalogued under Browser DevTools & extensions on PulseGate.

Who is Close New Duplicate Tabs for?

Close New Duplicate Tabs is an open-source project built for firefox users who want automatic duplicate-tab cleanup.

Is Close New Duplicate Tabs free?

Yes — Close New Duplicate Tabs is open source under the Open Source license and free to use.

What platforms does Close New Duplicate Tabs run on?

Close New Duplicate Tabs runs on the web and embeddable surfaces.

Is Close New Duplicate Tabs still active?

Unverified. Close New Duplicate Tabs has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

What are alternatives to Close New Duplicate Tabs?

Similar projects tracked by PulseGate include Close duplicate tabs, Duplicate Tab Closer, and Duplicate Tab.

Who makes Close New Duplicate Tabs?

Close New Duplicate Tabs is developed by sonnenfell.

How long has Close New Duplicate Tabs been around?

Close New Duplicate Tabs first shipped in 2025.

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Close New Duplicate Tabs

Name: Close New Duplicate Tabs
Author: sonnenfell

github.comBrowser DevTools & extensions

Close New Duplicate Tabs is an open-source Firefox WebExtension that automatically closes newly created tabs when they duplicate an existing tab. It preserves tabs that were already open before becoming duplicates by default and offers installation through Firefox Add-ons.

Open SourceWebEmbeddable

Visit github.com

2alternatives

5features

2025since

Overview

5 features

In the Browser DevTools & extensions space, Close New Duplicate Tabs takes a focused approach. It focuses on preventing newly opened duplicate browser tabs from cluttering Firefox. Close New Duplicate Tabs is an open-source project aimed at firefox users who want automatic duplicate-tab cleanup. The project is open source (Open Source). It runs on the web and embeddable surfaces.

It is developed by sonnenfell, and it first shipped in 2025. Key capabilities include duplicate tab detection, automatic tab closing, and existing tab preservation.

Summary written by a language model from the project’s public pages.

Duplicate tab detection
Automatic tab closing
Existing tab preservation
Firefox Add-ons installation
Configurable behavior

Built with & integrations

Runs on

BrowserEmbeddable

Trust & compliance

License

Open Source

Verified signals

HTTPSPrivacy Policy Terms of ServiceOpen SourceFree tierStore-verified publisher

Legal

Indexing history

What PulseGate has recorded for this listing

Indexed11 Sep · 15:51 UTC
Close New Duplicate Tabs verified via Firefox Add-ons
Source: Firefox Add-ons · Open

Frequently asked questions about Close New Duplicate Tabs

What does Close New Duplicate Tabs do?: Close New Duplicate Tabs focuses on preventing newly opened duplicate browser tabs from cluttering Firefox. It is catalogued under Browser DevTools & extensions on PulseGate.
Who is Close New Duplicate Tabs for?: Close New Duplicate Tabs is an open-source project built for firefox users who want automatic duplicate-tab cleanup.
Is Close New Duplicate Tabs free?: Yes — Close New Duplicate Tabs is open source under the Open Source license and free to use.
What platforms does Close New Duplicate Tabs run on?: Close New Duplicate Tabs runs on the web and embeddable surfaces.
Is Close New Duplicate Tabs still active?: Unverified. Close New Duplicate Tabs has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
What are alternatives to Close New Duplicate Tabs?: Similar projects tracked by PulseGate include Close duplicate tabs, Duplicate Tab Closer, and Duplicate Tab.Close duplicate tabs Duplicate Tab Closer Duplicate Tab
Who makes Close New Duplicate Tabs?: Close New Duplicate Tabs is developed by sonnenfell.
How long has Close New Duplicate Tabs been around?: Close New Duplicate Tabs first shipped in 2025.

At a glance

Pricing: Open Source
Platforms: Web
Languages: English
License: Open Source
Built for: Firefox users who want automatic duplicate-tab cleanup
Model: Open source
Solves: Preventing newly opened duplicate browser tabs from cluttering Firefox.

Registered as

Firefox Add-ons: close-new-duplicate-tabs

Developer

sonnenfell

Index record

Indexed: 11 Sep 2026
Lifecycle: Alive
Last seen: 11 Sep 2026

Identity audit (13)

Slug: close-new-duplicate-tabs-github-com
Lifecycle state recorded: 11 Sep 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 11 Sep 2026
Timeline basis: Indexed-at chronology. This listing's first-seen date was written by the catalog backfill, not observed here, so it is not treated as a sighting.
Name from: Written by a language model from the project's public pages.
Category from: Assigned by a language model.
Summary from: Written by a language model from public pages.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 11 Sep 2026
Canonical URL: https://github.com/sonnenfell/firefox-new-duplicate-tab-closer

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