WebDriverException: Message: invalid argument: can't kill an exited process with GeckoDriver, Selenium and Python on RaspberryPi3

Question

Server: Raspberry Pi 3
OS: Dietpi - version 159
Geckodriver version: 0.22 for arm
Firefox version: 52.9.0
Python version: 3.5
Selenium version: 3.14.1 <

Answer 1

As Nico and jay have stated you need to check the logs to see the details of the error. As you might use different systems, you can specify the path where the log is stored (i.e. "/tmp/geckodriver.log").

from selenium import webdriver
firefox_options = webdriver.firefox.webdriver.Options()
driver = webdriver.Firefox(log_path="/tmp/geckodriver.log", 
                           options=firefox_options)

In my particular case, what the log said was:

Error: no DISPLAY environment variable specified

That was resolved adding in the options the headless mode before starting the driver. With the line:

firefox_options.set_headless()