Installation

Since Firefox removed the internal component that loads legacy extensions, installing Tab Mix Plus (or any other legacy extension) needs third-party helper scripts. The short version of why is in Why we need it.

Tip

If you are using Waterfox browser, it ships with a built-in Bootstrap Loader, so you only need to install the firefox-scripts configuration files if you use userChromeJS scripts. If you only restyle the browser with userChrome.css and run no scripts or legacy extensions, Waterfox's built-in loader may be all you need.

Install Firefox Scripts

Please follow the instructions below step-by-step to install the scripts. The extension will not work if you install any files in the wrong location.

Installer and updater

firefox-scripts installs and keeps the helper scripts up to date. Once you approve the install, the small native installer automatically extracts both packages (fx-folder.zip and utils.zip) and copies each file to its right location in the browser. From then on, the in-browser updater keeps them current automatically as new versions are released. Background and rationale live on the Installer & auto-updater page; here is how to use them.

The installer

Download the installer for your OS from the firefox-scripts releases page: installer_win.exe (Windows), installer_linux / installer_linux_aarch64 (Linux), or installer_mac (macOS).

Run the downloaded installer. It connects to a running Firefox-family browser (Firefox, Waterfox, Zen Browser, LibreWolf, or Floorp), opens an install screen in a browser tab, and lets you pick which browser to set up.

Note

The installer is currently unsigned, so on Windows SmartScreen may show "Windows protected your PC" on first run. Click More info and then Run anyway to continue, and approve the single UAC prompt if it appears (one checksum-verified elevation, for the copy step only).

Choose the components to install:

• Configuration files (config.js, config-prefs.js): copied to the browser's installation directory.
• Utils (the chrome scripts): copied to your profile's chrome/utils/ directory.

Note

Install both packages. The configuration files alone load nothing, and the utils alone are never loaded. See Can I install only the configuration files?.

Click Install, wait for completion, then Restart the browser when prompted.

The installer automates the manual steps further down this page. It fetches fx-folder.zip and utils.zip from the latest release itself and copies each package to its place: the configuration files to the browser installation directory, and the utils to chrome/utils/ in every profile you set up. Installing by hand below does the same thing file by file.

The installer is a one-shot setup tool: it installs only the components you pick and does not leave behind any other files, background processes, or scheduled tasks. After the install completes you can delete the downloaded executable. Nothing else was installed besides the configuration files and scripts you chose.

The updater

Once installed, the scripts keep themselves current without you re-running the installer:

• Daily check. The updater (a small privileged script that lives inside the browser) checks once a day whether a newer version of the scripts or configuration files has been published.
• Notification tab. When an update is available, the updater opens a tab showing what would change. You can install the update right there, skip it for the day, or permanently ignore a specific update.
• Your choices. Install the update, Remind me Tomorrow, or Don't show again for this update (per package). Each choice and the preferences behind it are explained in Installer and auto-updater.
• In-tab install. Applying an update downloads the new packages and copies them into place inside the browser. No installer download needed. Updating the configuration files, which live in admin-protected folders (e.g. Program Files on Windows), triggers a single elevation prompt via a small helper that ships with the update.
• Manual update. You can always open the updater manually from the browser menu, or download the utils.zip / fx-folder.zip packages directly from the update tab.

Prefer to install by hand? Follow the download and installation steps below.

Download latest scripts

It is recommended to check periodically, or at least with every Firefox update, if new Firefox Scripts are available. You should download the latest version of the scripts from the links below.

• Download configuration files
• Download utils

utils.zip and fx-folder.zip are published with every build on the firefox-scripts repository. The links above always point at the latest build.

Caution

The original scripts were created by @xiaoxiaoflood, but the firefox-scripts repository is no longer maintained, and the code may be outdated.
Always use firefox scripts from the links above.

Install config script

Open about:support and locate the path to your Application Binary and Profile Folder

Note

Application Binary folder Is Firefox root directory (the folder that contains firefox.exe). for clarity, this text uses the terms Firefox root directory
Profile Folder is where Firefox stores your bookmarks, passwords and other user data. You can find more information about it in this article

Copy configuration files to your Firefox root directory.
fx-folder.zip files are packed with paths used by Firefox for Windows, Linux and macOS users should follow the instructions below. the zip file contain the following files:

• config.js - This file should be copied to the directory that contains firefox.exe, referred to as PATH TO FIREFOX.EXE.
• config-prefs.js - This file should be copied to [PATH TO FIREFOX.EXE]/defaults/pref.

IMPORTANT

Windows

Note:
The default path to Firefox on Windows is typically:

64-bit Firefox: C:\\Program Files\\Mozilla Firefox\\
32-bit Firefox: C:\\Program Files (x86)\\Mozilla Firefox\\

Verify the path:
Check the actual path to your Firefox root directory. If it differs from the default, replace the path accordingly in the following instructions.

Copy the configuration files extracted from fx-folder.zip:

• copy the file config.js to [PATH TO FIREFOX.EXE]\\config.js.
• copy the file config-prefs.js to [PATH TO FIREFOX.EXE]\\defaults\\pref\\config-prefs.js

Linux

Note:
The default path to Firefox on Linux is typically /usr/lib/firefox/.

Verify the path:
Check the actual path to your Firefox root directory. If it differs from /usr/lib/firefox/, replace the path accordingly in the following instructions.

Copy the configuration files extracted from fx-folder.zip:

• copy config.js to /usr/lib/firefox/config.js
• copy config-prefs.js to /usr/lib/firefox/browser/defaults/preferences/config-prefs.js

Linux with Snap

Compatibility Note:
Firefox snap for Linux versions prior to 108 are not supported.

Instructions for Firefox snap 108 or newer

Verify installation path:
If you're uncertain about the installation path of your Firefox snap, use the command snap list firefox in your terminal to check.

Copy the configuration files extracted from fx-folder.zip:

• copy config.js to /etc/firefox/config.js
• copy config-prefs.js to /etc/firefox/defaults/pref/config-prefs.js

You may have to create the sub folders /defaults/pref

macOS

Note:
The default path to Firefox on macOS is typically Firefox.app/Contents/Resources.

Verify the path:
Check the actual path to your Firefox root directory. If it differs from Firefox.app/Contents/Resources, replace the path accordingly in the following instructions.

Copy the configuration files extracted from fx-folder.zip:

• copy config.js to Firefox.app/Contents/Resources/config.js
• copy config-prefs.js to Firefox.app/Contents/Resources/defaults/pref/config-prefs.js

Install utils

Remember, the utils script needs to be installed separately in each profile where you want to use Tab Mix Plus. This differs from the main config script, which only requires installation once in your Firefox root directory (containing firefox.exe). The reason for this distinction is that each profile maintains its own settings and data, and the utils script plays a vital role in ensuring Tab Mix Plus works seamlessly within each individual profile.

1. Locate your Profile Folder as described in the previous step.

2. Create chrome folder in your Profile Folder (if one does not exist).

3. Extract utils folder inside the chrome folder, the result should be [PROFILE_NAME]/chrome/utils, all the files should be in the utils folder (see the screenshot below).
   Make sure all the files you see in the screenshot below are in the utils folder and that utils folder is inside chrome folder.

4. Open about:support page and click Clear startup cache… to force Firefox to load the installed scripts on the next startup.

Removing the scripts

1. Remove config.js and defaults/pref/config-prefs.js from the Firefox root directory.
2. Remove chrome/utils from each profile (your own .uc.js scripts and userChrome.css in chrome/ stay untouched).
3. Restart the browser.

The updater goes away with the utils, so nothing will try to re-install anything. If you still have config.js and config-prefs.js in the browser root after this, Firefox will still try to run AutoConfig on the next start. Remove those too, or it will log that config.js is missing.

Browser compatibility

These scripts are validated on every release in CI against the browsers below. Anything not listed here may work, but is not covered by the release gates.

Browser	Notes
Firefox (stable, ESR, Developer Edition, Nightly)	Fully supported. Nightly is the leading edge (see the current Nightly version below).
Waterfox	Ships its own Bootstrap Loader, so ours skips loading it (loading both would double-register and break legacy add-ons). userChrome.js and the updater still work.
Zen Browser	No special handling needed.
LibreWolf	No special handling needed.
Floorp	No special handling needed.

A browser must be running when the installer runs. Detection uses process scanning and lock-file inspection.

In three steps

1. Download the installer for your OS from the latest release.
2. Run it and pick the browsers and components to install in the tab it opens.
3. Restart the browser. From then on, updates arrive on their own.