web-ext command reference

--as-needed

When you edit and save a source file, rebuild the extension. This enables you to continuously create a package with the most up-to-date source code.

Environment variable: $WEB_EXT_AS_NEEDED=true

--overwrite-dest, -o

Overwrite the destination package file if it exists. Without this option, web-ext exits with an error if the destination file exists.

Environment variable: $WEB_EXT_OVERWRITE_DEST=true

--filename, -n

Name of the created extension package file. In this option, the values defined in manifest.json can be used by enclosing them with { }. The default value is {name}-{version}.zip.

Environment variable: $WEB_EXT_FILENAME

--output, -o

The type of output to generate when reporting on errors. Choices: json or text.

Environment variable: $WEB_EXT_OUTPUT

--metadata

Output only metadata about the extension in JSON.

Environment variable: $WEB_EXT_METADATA=true

--pretty

Format the JSON output so that it's easier to read. This only applies when --output is set to json.

Environment variable: $WEB_EXT_PRETTY=true

--self-hosted

Declares that your extension will be self-hosted. This disables messages related to hosting on addons.mozilla.org.

Environment variable: $WEB_EXT_SELF_HOSTED=true

--boring

Disables colorful shell characters so that the output only contains plain text.

Environment variable: $WEB_EXT_BORING=true

--warnings-as-errors, -w

Treat warnings as errors by exiting non-zero for warnings.

Environment variable: $WEB_EXT_WARNINGS_AS_ERRORS=true

--adb-bin

The path to the ADB (Android Device Bridge) executable on the machine you are running web-ext from. By default, the adb executable is located on your PATH.

Environment variable: $WEB_EXT_ADB_BIN

--adb-device, --android-device

The ID of your target Android device. If you do not specify this option, web-ext will list the IDs of each device connected. If you don't see a list of connected devices, ensure yours is set up for development.

Example:

web-ext run --target=firefox-android --android-device FA4AX0201736

Environment variable: $WEB_EXT_ADB_DEVICE

--adb-host

The host name to use when connecting to an Android device with ADB (Android Device Bridge). By default, this is discovered automatically.

Environment variable: $WEB_EXT_ADB_HOST

--adb-port

Network port to use when connecting to an Android device with ADB (Android Device Bridge). This will be discovered automatically by default.

Environment variable: $WEB_EXT_ADB_PORT

--adb-remove-old-artifacts

Forces web-ext to remove any old artifacts discovered at startup. Otherwise, web-ext run provides a warning if it finds old artifacts on the adb device.

Normally, when web-ext exits, it removes all the temporary files written to the target adb device. However, this may not happen, for example, when the device is disconnected before web-ext exits.

Environment variable: $WEB_EXT_ADB_REMOVE_OLD_ARTIFACTS

--browser-console, -bc

Open a browser console on startup so you can see log messages for your extension. Example:

web-ext run --browser-console

Environment variable: $WEB_EXT_BROWSER_CONSOLE=true

Note: The browser console may not show all debugging output from content scripts. Use the web console when debugging content scripts.

--devtools

Open the Developer Tools for the installed extension on startup. See this documentation for more information. Example:

web-ext run --devtools

Note: The opened Developer Tools may not show all debugging output from content scripts. Use the web console when debugging content scripts.

--firefox, -f

A version of Firefox Desktop to run the extension in. The value is an absolute path to the Firefox executable or an alias string. If not specified, the extension runs in the system's default installation of Firefox.

Here is an example specifying a full path to a Firefox executable on Windows:

--firefox="C:\Program Files\Mozilla Firefox\firefox.exe"

Here is an example specifying an executable path on Mac OS:

--firefox=/Applications/FirefoxNightly.app/Contents/MacOS/firefox-bin

You can also use aliases like this:

--firefox=beta

Here are all available aliases and the executables they map to:

Flatpak users can use this option with the value flatpak:org.mozilla.firefox (where org.mozilla.firefox is the Flatpak application ID for Firefox on Flathub):

web-ext run --firefox=flatpak:org.mozilla.firefox

Environment variable: $WEB_EXT_FIREFOX

--firefox-apk

The APK name for Firefox on your Android device. If more than one Firefox APK is installed, web-ext shows a list of values to choose from. Otherwise, web-ext uses the available APK.

Example:

web-ext run --target=firefox-android --firefox-apk=org.mozilla.firefox

Environment variable: $WEB_EXT_FIREFOX_APK

--firefox-profile, -p

The base Firefox profile to run the extension in as a string containing your profile name or an absolute path to its directory. The profile you specify is copied into a new temporary profile, and the settings required for web-ext to function are added.

If a profile is not specified, it runs the extension using a new temporary profile.

Environment variable: $WEB_EXT_FIREFOX_PROFILE

--profile-create-if-missing

Create the profile directory (specified by the --firefox-profile or --chromium-profile options) if it does not exist.

Environment variable: $WEB_EXT_PROFILE_CREATE_IF_MISSING

--keep-profile-changes

Save any changes made to the profile directory (specified by --firefox-profile). Without this option, profile changes are not saved.

Environment variable: $WEB_EXT_KEEP_PROFILE_CHANGES=true

--no-reload

Do not automatically reload the extension in the browser as you edit and save source files.

Environment variable: $WEB_EXT_NO_RELOAD=true

--pre-install

Install the extension into the profile before starting the browser. This is a way to support Firefox versions 49 or earlier, as they don't support remote installation. Specifying this option implies --no-reload.

Environment variable: $WEB_EXT_PRE_INSTALL=true

--pref

Customize any Firefox preference without creating or modifying the profile. Use the equal sign to set values, for example:

--pref general.useragent.locale=fr-FR

Specify this option multiple times to set more than one preference.

Environment variable: $WEB_EXT_PREF

--target, -t

Specify the application to run your extension in. Specify this option multiple times to run the extension in each application concurrently.

Here are the supported targets:

If no target is specified, the extension runs in firefox-desktop.

Environment variable: $WEB_EXT_TARGET

--args, --arg

Additional CLI options passed to the browser binary. Examples:

web-ext run --arg="--search=mozilla" --arg="--new-tab=https://duckduckgo.com"

web-ext run --arg="--remote-debugging-port=9229" --target chromium

--chromium-binary

Path or alias to a Chromium executable such as google-chrome, google-chrome.exe, or opera.exe.
If not specified, the default Google Chrome is used.

--chromium-profile

Path to a custom Chromium profile.

--start-url

Open a tab at the specified URL when the browser starts. Example:

web-ext run --start-url www.mozilla.com

To open several tabs, declare this option multiple times. Example:

web-ext run --start-url www.mozilla.com --start-url developer.mozilla.org

Environment variable: $WEB_EXT_START_URL

--watch-file, --watch-files

A list of files that should be watched for changes. This is useful if you want web-ext to watch for changes to specific files without watching the extension directory tree, e.g., the build output from a module bundler.

web-ext run --watch-file dist/background.js dist/content-script.js

--watch-ignored

A list of paths and globs patterns that should not be watched for changes. Use this to prevent web-ext from watching part of the extension directory tree, e.g., the node_modules folder.

web-ext run --watch-ignored dir1/to/file.js dir2/*.js dir3/**

--api-key

Your API key (JWT issuer) for accessing the addons.mozilla.org API. This should always be a string.

Environment variable: $WEB_EXT_API_KEY

--api-secret

Your API secret (JWT secret) from addons.mozilla.org API. This should always be a string.

Environment variable: $WEB_EXT_API_SECRET

--approval-timeout

Number of milliseconds to wait for approval before giving up. Set to 0 to disable the wait for approval. Defaults to timeout if not set. Defaults to 15 minutes (900000 ms).

Environment variable: $WEB_EXT_APPROVAL_TIMEOUT

--amo-base-url

A string containing the add-on submission API base URL. If not specified, defaults to the production API: https://addons.mozilla.org/api/v5/.

Environment variable: $WEB_EXT_AMO_BASE_URL

--api-proxy

A proxy host to use for all API connections. Example: https://yourproxy:6000. Read more about how proxy requests work. There is a separate section about signing in a restricted environment if the proxy approach doesn't work for you.

Environment variable: $WEB_EXT_API_PROXY

--channel

The channel the extension is signed in. This option is required.

The allowed values for channel are:

An example of using the --channel option is to create a beta version for an extension listed on addons.mozilla.org.

Environment variable: $WEB_EXT_CHANNEL

--timeout

Number of milliseconds to wait before giving up on a response from Mozilla's web service. This should always be a number. Defaults to 5 minutes (300000 ms)

Environment variable: $WEB_EXT_TIMEOUT

--amo-metadata

The path to a JSON file containing an object with metadata for the extension's addons.mozilla.org (AMO) listing.

Metadata is required for the first version of an extension listed on AMO. This metadata can include any of the properties of the addons.mozilla.org add-on API Create request JSON object. However:

• "categories", "summary" and the version's "license" properties must be provided.
• Translated fields must include at least one locale.

A minimal JSON file looks like this:

{
  "summary": {
    "en-US": "A short sentence that explains what the extension does."
  },
  "categories": [
    "other"
  ],
  "version": {
    "license": "MPL-2.0"
  }
}

The "license" field accepts one of these SPDX identifiers: MPL-1.1, MPL-2.0, GPL-2.0-or-later, GPL-3.0-or-later, LGPL-2.1-or-later, LGPL-3.0-or-later, MIT, BSD-2-Clause, cc-all-rights-reserved, CC-BY-3.0, CC-BY-NC-3.0, CC-BY-NC-ND-3.0, CC-BY-NC-SA-3.0, CC-BY-ND-3.0, CC-BY-SA-3.0, and all-rights-reserved.

When publishing an extension update metadata isn't required. If metadata isn't provided, the license specified for the first version is reused. However, any of the properties of the addons.mozilla.org add-on API Version Create request JSON object can be provided. For example, if you want to specify "approval_notes", the JSON file looks like this:

{
  "version": {
    "approval_notes": "Information that helps Mozilla reviewers if they review the add-on. Only visible to Mozilla."
  }
}

Environment variable: $WEB_EXT_AMO_METADATA

--upload-source-code

The path to an archive file containing human-readable source code for this submission. See Source code submission for details.

Environment variable: $WEB_EXT_UPLOAD_SOURCE_CODE