[Python] How do I get Selenium on python to connect to an existing instance of Firefox - I am...

I am trying to use Selenium to connect to existing instance of Firefox - the documentation says to use something like this

options=webdriver.FirefoxOptions()
options.binary_location = r'C:\Program Files\Mozilla Firefox\firefox.exe'


webdriver_service = Service(r'c:\tmp\geckodriver.exe')
driver = webdriver.Firefox(service = webdriver_service, service_args=['--marionette-port', '2828', '--connect-existing'])


However, I get the error

driver = webdriver.Firefox(service = webdriver_service, service_args=['--marionette-port', '2828', '--connect-existing'])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: WebDriver.__init__() got an unexpected keyword argument 'service_args'


I see other questions about "unexpected keyword argument", they say latest versions of Selenium has other ways of passing arguments through Options.

I tried

options.add_argument('--marionette-port')
options.add_argument('2828')
options.add_argument('--connect-existing')


But it still seems to create a new instance of Firefox

I have started firefox with the following arguments

"C:\Program Files\Mozilla Firefox\firefox.exe" -marionette -start-debugger-server 2828

How do I fix this?


These are my versions

Python version

python --version
Python 3.12.2


Selenium version

pip show selenium
Name: selenium
Version: 4.18.1


Geckodriver version

geckodriver --version
geckodriver 0.34.0 (c44f0d09630a 2024-01-02 15:36 +0000)


Firefox 123.0 (64-bit)

Windows 11

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