Window Merger

Window Merger

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.

Window Merger promo image
What is Window Merger?

Window Merger is a streamlined Firefox add-on dedicated to merging browser windows. It provides the flexibility to merge all open windows or selected ones, using right-click context menu or keyboard shortcuts. Additionally, Window Merger is compatible with Private Windows, maintaining your privacy by keeping private and normal windows separate. Its preferences screen integrates seamlessly within the browser's Extensions page, fully supporting dark mode. Great for all users, especially those who prefer keyboard functionality and want an organized browsing environment.

Stats date:
By: Martijn
Users: 740 ▼ -4
Rating: 4.67 (12)
Version: 0.6.0 (Last updated: 2020-12-25)
Creation date: 2019-08-31
Weekly download count: 21
Firefox on Android: No
Manifest version: 2
  • tabs
  • menus
  • storage
Size: 12.68K
URLs: Website
Risk impact: Moderate risk impact
Risk likelihood: Low risk likelihood

Other platforms

Not available on Chrome
Not available on Edge

Window Merger was created to address how people want to merge browser windows together after a long browsing session. Simply right click to open Firefox’s context menu when multiple windows are open, pick the window you want to merge with, and done!

It focusses on merging windows alone, but gives some usability choices that other alternatives do not have like user defined keyboard shortcuts and accessibility through the browser’s own Tools menu.

Have a look at the screenshots to see what is on offer!

  • Window Merger does not require you to merge everything. Often people wanted to merge only specific windows together, so that choice had to be given.
  • Window Merger does not require you to use a mouse. It offers configurable keyboard actions for those who prefer it.
  • Window Merger works together with Private Windows. Private windows are kept separate from normal windows in all features. A private window will only ever merge with another private window, making sure tabs do not leak into non-private space.
Have a look at the screenshots to see what is on offer!

Special care was taken to make sure the extension would fit well within the browser. Its preferences screen integrates with the Extensions page really well, and adheres to dark mode if chosen by the user. Releases are also tested with ESR versions of Firefox to be as accessible as possible.

Beside this Window Merger tries to stick to the Linux mantra of “Do One Thing and Do It Well”.

Some other tab management extensions you may like:

  • FoxyTab — for the all in one thing. If Window Merger does not satisfy your habits, chances are a configuration of FoxyTab exists that does!
  • Duplicate Tabs Closer — for cleaning tabs after merging windows. If getting rid only of windows is not enough, Duplicate Tabs Closer can help you to clear out tabs as well!
User reviews
User reviews summary
These summaries are automatically generated weekly using AI based on recent user reviews. Firefox Browser Add-ons does not verify user reviews, so some user reviews may be inaccurate, spammy, or outdated.
  • Works great and is fast
  • Can merge two windows
  • Particularly effective when assigned keyboard shortcuts
  • Useful for managing multiple open tabs
  • Simple and does the job perfectly
  • Difficult to find the 'options' or 'button' in the browser window
  • Not present in 'tools' section of browser
  • Issues with Firefox Quantum
Most mentioned
  • Fast and effective
  • Helpful for managing multiple tabs
  • Challenges in finding and using features
  • Excellent with Waterfox Classic
View all user reviews
Risk impact

Window Merger may not be safe to use and it requires some risky permissions. Exercise caution when installing this add-on. Review carefully before installing.

Risk likelihood

Window Merger has earned a fairly good reputation and likely can be trusted.

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