I am running selenium grid within a docker container to test some processes in a Django application.

The first time I run the test, after docker-compose up I get

docker-compose exec web coverage run manage.py test researcher_UI --tag=login
Found 2 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
..E
======================================================================
ERROR: tearDownClass (researcher_UI.tests.test_processes.login_process.WebSiteOpensTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/app/researcher_UI/tests/test_processes/login_process.py", line 28, in tearDownClass
    cls.firefox.quit()
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 469, in quit
    self.execute(Command.QUIT)
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 347, in execute
    self.error_handler.check_response(response)
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/errorhandler.py", line 229, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.WebDriverException: Message: Failed to decode response from marionette


----------------------------------------------------------------------
Ran 2 tests in 7.473s

FAILED (errors=1)
Destroying test database for alias 'default'...

Please note the test ran successfully but errored when quiting the driver.

If I run the test again it won’t even open a browser instance:

docker-compose exec web coverage run manage.py test researcher_UI --tag=login
Found 2 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
E
======================================================================
ERROR: setUpClass (researcher_UI.tests.test_processes.login_process.WebSiteOpensTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/app/researcher_UI/tests/test_processes/login_process.py", line 21, in setUpClass
    cls.firefox = webdriver.Remote(
                  ^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 208, in __init__
    self.start_session(capabilities)
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 292, in start_session
    response = self.execute(Command.NEW_SESSION, caps)["value"]
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/webdriver.py", line 347, in execute
    self.error_handler.check_response(response)
  File "/usr/local/lib/python3.11/site-packages/selenium/webdriver/remote/errorhandler.py", line 229, in check_response
    raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.SessionNotCreatedException: Message: Could not start a new session. Error while creating session with the driver service. Stopping driver service: Could not start a new session. Response code 500. Message: Process unexpectedly closed with status 1 
Host info: host: '06a8ec0d9b6d', ip: '172.18.0.3'
Build info: version: '4.19.1', revision: 'abe0ee07dc'
System info: os.name: 'Linux', os.arch: 'amd64', os.version: '6.6.22-linuxkit', java.version: '17.0.10'
Driver info: driver.version: unknown
Build info: version: '4.19.1', revision: 'abe0ee07dc'
System info: os.name: 'Linux', os.arch: 'amd64', os.version: '6.6.22-linuxkit', java.version: '17.0.10'
Driver info: driver.version: unknown
Stacktrace:
    at org.openqa.selenium.grid.node.config.DriverServiceSessionFactory.apply (DriverServiceSessionFactory.java:221)
    at org.openqa.selenium.grid.node.config.DriverServiceSessionFactory.apply (DriverServiceSessionFactory.java:71)
    at org.openqa.selenium.grid.node.local.SessionSlot.apply (SessionSlot.java:147)
    at org.openqa.selenium.grid.node.local.LocalNode.newSession (LocalNode.java:464)
    at org.openqa.selenium.grid.distributor.local.LocalDistributor.startSession (LocalDistributor.java:651)
    at org.openqa.selenium.grid.distributor.local.LocalDistributor.newSession (LocalDistributor.java:570)
    at org.openqa.selenium.grid.distributor.local.LocalDistributor$NewSessionRunnable.handleNewSessionRequest (LocalDistributor.java:830)
    at org.openqa.selenium.grid.distributor.local.LocalDistributor$NewSessionRunnable.lambda$run$1 (LocalDistributor.java:790)
    at java.util.concurrent.ThreadPoolExecutor.runWorker (None:-1)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run (None:-1)
    at java.lang.Thread.run (None:-1)

----------------------------------------------------------------------
Ran 0 tests in 0.510s

FAILED (errors=1)
Destroying test database for alias 'default'...

This is my Django test:

@tag("selenium", "login")
class WebSiteOpensTests(LiveServerTestCase):
    LiveServerTestCase.host = "web"

    @classmethod
    def setUpClass(cls):
        super().setUpClass()
        options = Options()
        cls.firefox = webdriver.Remote(
            command_executor="http://selenium:4444", options=options
        )
        cls.firefox.implicitly_wait(10)

    @classmethod
    def tearDownClass(cls):
        cls.firefox.quit()
        super().tearDownClass()

    def test_visit_home_age(self):
        self.firefox.get(f"{self.live_server_url}")
        self.assertIn(self.firefox.title, "Site Title")

    def test_visit_login_page(self):
        self.firefox.get(f"{self.live_server_url}/accounts/login/")
        self.assertIn(self.firefox.title, "Login")

This is my docker-compose.yml:

services:
  db:
      image: postgres
      volumes:
        - postgres_data:/var/lib/postgresql/data/
      environment:
        - POSTGRES_USER=postgres
        - POSTGRES_PASSWORD=postgres
      ports:
        - "5432"
      healthcheck:
        test: "exit 0"

  web: 
    build:
      context: .
      dockerfile: Dockerfile
    command: python manage.py runserver 0.0.0.0:8000
    volumes:
      - ./webcdi:/app
    ports:
      - "8000:8000"
    env_file:
      - .env
    depends_on:
      - db
      
  mail:
    platform: linux/x86_64
    image: mailhog/mailhog:latest
    ports:
      - "8025:8025"

  pgadmin:
    image: dpage/pgadmin4:latest
    depends_on:
      - db
    ports:
      - "5051"
    environment:
      PGADMIN_DEFAULT_EMAIL: ${PGADMIN_DEFAULT_EMAIL}
      PGADMIN_DEFAULT_PASSWORD: ${PGADMIN_DEFAULT_PASSWORD}

  selenium:
    image: selenium/standalone-firefox:latest
    ports:
      - 4444:4444

    
volumes:
  postgres_data:

I have seen posts suggesting that I need to give selenium 2gb of RAM which I have previously tried by adding (but it made no difference).

build:
   context .
   memory '2gb'

My docker desktop is set up to allow 16GB memory.

This was working a week ago, and the only thing I’ve changed is upgraded to the latest version of docker desktop (4.29.0) from 4.24 but I find it hard to believe this is the issue.

Any help most welcome