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

in my case, I was running test cases as root

geckodriver.log

1576076416677   mozrunner::runner       INFO    Running command: "/usr/bin/firefox" "-marionette" "-foreground" "-no-remote" "-profile" "/tmp/rust_mozprofilenCbl2e"
Running Firefox as root in a regular user's session is not supported.  ($HOME is /home/seluser which is owned by seluser.)
1576077143004   mozrunner::runner       INFO    Running command: "/usr/bin/firefox" "-marionette" "-foreground" "-no-remote" "-profile" "/tmp/rust_mozprofile7wpSQ7"
1576077143689   addons.webextension.screenshots@mozilla.org     WARN    Loading extension 'screenshots@mozilla.org': Reading manifest: Invalid extension permission: mozillaAddons
1576077143689   addons.webextension.screenshots@mozilla.org     WARN    Loading extension 'screenshots@mozilla.org': Reading manifest: Invalid extension permission: telemetry
1576077143689   addons.webextension.screenshots@mozilla.org     WARN    Loading extension 'screenshots@mozilla.org': Reading manifest: Invalid extension permission: resource://pdf.js/
1576077143689   addons.webextension.screenshots@mozilla.org     WARN    Loading extension 'screenshots@mozilla.org': Reading manifest: Invalid extension permission: about:reader*
1576077145372   Marionette      INFO    Listening on port 35571
1576077145423   Marionette      WARN    TLS certificate errors will be ignored for this session
1576077200207   mozrunner::runner       INFO    Running command: "/usr/bin/firefox" "-marionette" "-foreground" "-no-remote" "-profile" "/tmp/rust_mozprofilenhoHlr"
Running Firefox as root in a regular user's session is not supported.  ($HOME is /home/seluser which is owned by seluser.)

i could get around by

cd /home
chown -R  root seluser

i woundnt say its correct but it got my job done