---
id: marionette-driver
version: "3.7.1"
license: MPL
license_treatment: copyleft
maintenance: active
---

# marionette-driver — Marionette Driver

License: copyleft · Maintenance: active · Downloads: 171.3K/mo

## What it is and what it does

Marionette Driver is a Python client library that communicates with Firefox's Marionette automation protocol, allowing you to control a Firefox browser instance programmatically. It depends on mozrunner (for launching Firefox), mozversion (for version detection), and psutil (for process management). The package supports Python 3.8, 3.9, 3.10, 3.11, 3.12, and 3.13 on macOS, Windows, and POSIX systems.

The library is explicitly marked as no longer supported in its own description, despite showing recent release activity. It was originally designed for browser automation and testing workflows, but the fact sheet does not clarify whether it remains the recommended tool or whether users should migrate to alternatives.

Use it for:

- Automated testing of Firefox-specific browser behavior and web application functionality.
- Scripting repetitive browser tasks like form filling, navigation, and screenshot capture in Firefox.
- Integration testing of web applications that require Firefox-specific features or compatibility verification.
- Headless Firefox automation for CI/CD pipelines and automated quality assurance workflows.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Marionette Driver provides a Python client for automating Firefox through the Marionette protocol, enabling programmatic browser control and testing.

No, not recommended for new projects. The package is explicitly marked as no longer supported and inactive, despite recent release dates. The description directs users to Mozilla's documentation, suggesting the project has been superseded or deprecated. Existing projects using it should evaluate migration to actively maintained alternatives.

## Install

pip install marionette-driver
uv add marionette-driver
poetry add marionette-driver

## Installing marionette-driver

Before you install: Low install friction with three lightweight runtime dependencies (mozrunner, mozversion, psutil). Maintenance status is active, though the package itself is marked as inactive in development status.

License in practice: Licensed under Mozilla Public License 2.0 (MPL), a copyleft license. You may use and modify the code, but derivative works and distributions must retain the same license terms.

Quickstart:

pip install marionette-driver

from marionette_driver.marionette import Marionette

client = Marionette('localhost')
client.start_session()

Requires a running Firefox instance with Marionette protocol enabled; Firefox must be launched with appropriate flags to accept Marionette connections.

Verify before relying:

- Whether the package is actively maintained despite the 'Inactive' development status classifier and the note that it is 'no longer supported'.
- Current compatibility with modern Firefox versions and whether the Marionette protocol remains the recommended approach for Firefox automation.
- Whether alternatives are now preferred for Firefox testing workflows.

## Package facts

- License: MPL (copyleft)
- Python support: supports_current
- Install friction: low
- Maintenance: active
- Downloads: 171.3K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

firefox automation python, browser automation marionette, firefox webdriver protocol, automated browser testing, firefox remote control, marionette protocol client, firefox test automation, deprecated, firefox-automation

[View on SkillFed](https://skillfed.io/packages/marionette-driver) · [View on PyPI](https://pypi.org/project/marionette-driver/)