TabOnce

Name: TabOnce
Author: dorian

TabOnce focuses an existing matching tab instead of opening a duplicate. You choose exactly which sites and URL patterns it applies to.

Overview

Firefox Add-ons Store

Daily users

Data as of 2026-09-10

Version:

1.2.0

Last updated: 2026-08-30

Features & Capabilities

TabOnce keeps duplicate tabs under control without affecting every page you visit.

Create opt-in rules for the websites and URL patterns that should only have one matching tab open. When TabOnce detects a duplicate, it closes the new tab and focuses the existing one instead.

Rules can:

Match literal or variable path segments
Treat deeper paths as the same page
Include or ignore query strings and fragments
Be enabled, disabled, and reordered
Optionally intercept same-site links when the destination is already open

For example, different views of the same GitHub pull request can share one tab, while separate pull requests remain distinct.

Site access is requested separately for each configured origin. TabOnce is fully open-source, and does not collect or transmit any personal data.

Review the full source code at https://github.com/dkarter/tab-once

User Growth & Download Statistics

Add-on

By:

dorian

Daily users:

Version:

1.2.0 Last updated: 2026-08-30

Version code:

6448119

Creation date:

2026-08-11

Firefox add-on GUID:

tab-once@dkarter.dev

Firefox add-on numeric ID:

3052307

Weekly download count:

Firefox on Android:

Risk:

Permissions:

Size:

49.50KB

URLs:

Website

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-09-10

Compare stats and ranking:

Ranking

# 134,697 ▲ 573

Other rankings

#211 in fragment keyword 11 ▼ 6

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Firefox add-on. Please use these information below to contact the Firefox add-on developer.

Developed by:

dorian

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/tabonce/

Website:

https://github.com/dkarter/tab-once

Is TabOnce Safe?

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

TabOnce requires a few sensitive permissions. Exercise caution before installing.

Risk impact analysis details

Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.

Risk likelihood

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Add-ons Store, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

TabOnce is recently added, and hasn't been around long enough for us to gather enough data to accurately assess its risk level.

Risk likelihood analysis details

High This extension was recently updated in the past month. New updates may not be stable or safe.
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