Window Merger

Name: Window Merger
Rating: 5 (16 reviews)
Author: Martijn

Merge specified browser windows into each other. Or all of them into one. Simply right click to open Firefox’s context menu when multiple windows are open, or configure a keyboard shortcut. All wrapped up in one tiny free extension.

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Features & Capabilities

Window Merger is designed to merge browser windows efficiently—either all at once or selectively—using a right-click Firefox context menu or configurable keyboard shortcuts. It focuses on window merging, while offering user-friendly options such as private-window safety, dark-mode integration, and a clean Extensions page experience.

The design emphasizes doing one thing well and staying accessible. It supports private windows merging, avoids mixing private and non-private spaces, is tested for ESR Firefox versions, and aligns with Linux workflows. It also references related tab-management extensions for users who want more options.

User Growth & Download Statistics

Add-on Developer Tools Privacy & Security Accessibility

By:

Martijn

Daily users:

718 -7

Rating:

5.00

(16)

Version:

0.7.2 Last updated: 2026-04-11

Version code:

6216480

Creation date:

2019-08-31

Risk:

Permissions:

Size:

22.68KB

URLs:

Website

Full description:

Source:

Firefox Add-ons Store

Data ingested on:

2026-06-15

Compare stats and ranking:

Ranking

# 4,005 ▼ 27

Other rankings

#26 in member keyword 13 #29 in windows keyword 40 #67 in configure keyword 25 ▼ 1#166 in choice keyword 16

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:

Martijn

Firefox Add-ons Store

https://addons.mozilla.org/firefox/addon/window-merger/

Website:

https://github.com/Zegnat/browserext-window-merger/issues

User Reviews

Users find Window Merger to be a simple, fast, and effective add-on that helps merge browser windows efficiently, especially valued by heavy tab users. Many praise its functionality and keyboard shortcut support. However, some users experience difficulty locating the add-on's interface or understanding its options, indicating a need for clearer guidance or documentation.

Pros

Effectively merges multiple browser windows, including the ability to merge just two windows rather than all.
Simple, slim, and fast functionality with keyboard shortcut support.
Highly appreciated by users who manage many tabs at once, providing better tab organization.
Outstanding performance on multiple browsers including Firefox Quantum and Waterfox Classic.
Easy to use via right-click on any tab.

Cons

Some users have difficulty locating the add-on's interface, options, or buttons, with confusion about where to access features.
Lack of clear instructions or guidance on how to use the extension's options leads to user uncertainty.

Recent reviews

Does the one simple task I need it to (right click, merge all tabs to this window). Operating on multiple screens is not a task to hunt down tabs anymore. Thank you!

by Da*****, 2026-04-08

by tz*****, 2026-01-25

by Da*****, 2025-06-29

View all user reviews ›

Is Window Merger 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.

Window Merger 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.

Window Merger is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
Medium **** ********* *** ******* ** *** **** * ******* *** ******* *** *** ** ****** ** *****
Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Good **** ********* *** **** **** *******