troubleshooting behat testing with DDEV and Chromedriver

behat.yml

default:
  suites:
    default:
      contexts:
        - FeatureContext
        - Drupal\DrupalExtension\Context\MinkContext

  gherkin:
    cache: ~
  extensions:
    DMore\ChromeExtension\Behat\ServiceContainer\ChromeExtension: ~
    Behat\MinkExtension:
      goutte: ~
      base_url: https://test-d9-site.ddev.site
      show_cmd: google-chrome %s
      javascript_session: chrome
      chrome:
#        api_url: "http://localhost:9222"
#        api_url: "http://test-d9-site.ddev.site:9222"
#        api_url: "http://test-d9-site.ddev.site:9515"
        api_url: "http://chromedriver:9222"
    Drupal\DrupalExtension:
      api_driver: drupal
      drupal:
        drupal_root: web/

config.yaml

name: test-d9-site
type: drupal9
docroot: web
php_version: "7.3"
webserver_type: nginx-fpm
router_http_port: "80"
router_https_port: "443"
xdebug_enabled: false
additional_hostnames: []
additional_fqdns: []
mariadb_version: "10.3"
provider: default
use_dns_when_possible: true
hooks:
  post-start:
  - exec: ../scripts/post-start.sh


# This config.yaml was created with ddev version v1.15.2
# webimage: drud/ddev-webserver:v1.15.2
# dbimage: drud/ddev-dbserver-mariadb-10.2:v1.15.1
# dbaimage: phpmyadmin/phpmyadmin:5
# However we do not recommend explicitly wiring these images into the
# config.yaml as they may break future versions of ddev.
# You can update this config.yaml using 'ddev config'.

# Key features of ddev's config.yaml:

# name: <projectname> # Name of the project, automatically provides
#   http://projectname.ddev.site and https://projectname.ddev.site

# type: <projecttype>  # drupal6/7/8, backdrop, typo3, wordpress, php

# docroot: <relative_path> # Relative path to the directory containing index.php.

# php_version: "7.3"  # PHP version to use, "5.6", "7.0", "7.1", "7.2", "7.3", "7.4"

# You can explicitly specify the webimage, dbimage, dbaimage lines but this
# is not recommended, as the images are often closely tied to ddev's' behavior,
# so this can break upgrades.

# webimage: <docker_image>  # nginx/php docker image.
# dbimage: <docker_image>  # mariadb docker image.
# dbaimage: <docker_image>

# mariadb_version and mysql_version
# ddev can use many versions of mariadb and mysql
# However these directives are mutually exclusive
# mariadb_version: 10.2
# mysql_version: 8.0

# router_http_port: <port>  # Port to be used for http (defaults to port 80)
# router_https_port: <port> # Port for https (defaults to 443)

# xdebug_enabled: false  # Set to true to enable xdebug and "ddev start" or "ddev restart"
# Note that for most people the commands
# "ddev exec enable_xdebug" and "ddev exec disable_xdebug" work better,
# as leaving xdebug enabled all the time is a big performance hit.

# webserver_type: nginx-fpm  # Can be set to apache-fpm or apache-cgi as well

# timezone: Europe/Berlin
# This is the timezone used in the containers and by PHP;
# it can be set to any valid timezone,
# see https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
# For example Europe/Dublin or MST7MDT

# additional_hostnames:
#  - somename
#  - someothername
# would provide http and https URLs for "somename.ddev.site"
# and "someothername.ddev.site".

# additional_fqdns:
#  - example.com
#  - sub1.example.com
# would provide http and https URLs for "example.com" and "sub1.example.com"
# Please take care with this because it can cause great confusion.

# upload_dir: custom/upload/dir
# would set the destination path for ddev import-files to custom/upload/dir.

# working_dir:
#   web: /var/www/html
#   db: /home
# would set the default working directory for the web and db services.
# These values specify the destination directory for ddev ssh and the
# directory in which commands passed into ddev exec are run.

# omit_containers: [db, dba, ddev-ssh-agent]
# Currently only these containers are supported. Some containers can also be
# omitted globally in the ~/.ddev/global_config.yaml. Note that if you omit
# the "db" container, several standard features of ddev that access the
# database container will be unusable.

# nfs_mount_enabled: false
# Great performance improvement but requires host configuration first.
# See https://ddev.readthedocs.io/en/stable/users/performance/#using-nfs-to-mount-the-project-into-the-container

# host_https_port: "59002"
# The host port binding for https can be explicitly specified. It is
# dynamic unless otherwise specified.
# This is not used by most people, most people use the *router* instead
# of the localhost port.

# host_webserver_port: "59001"
# The host port binding for the ddev-webserver can be explicitly specified. It is
# dynamic unless otherwise specified.
# This is not used by most people, most people use the *router* instead
# of the localhost port.

# host_db_port: "59002"
# The host port binding for the ddev-dbserver can be explicitly specified. It is dynamic
# unless explicitly specified.

# phpmyadmin_port: "8036"
# phpmyadmin_https_port: "8037"
# The PHPMyAdmin ports can be changed from the default 8036 and 8037

# mailhog_port: "8025"
# mailhog_https_port: "8026"
# The MailHog ports can be changed from the default 8025 and 8026

# webimage_extra_packages: [php7.3-tidy, php-bcmath]
# Extra Debian packages that are needed in the webimage can be added here

# dbimage_extra_packages: [telnet,netcat]
# Extra Debian packages that are needed in the dbimage can be added here

# use_dns_when_possible: true
# If the host has internet access and the domain configured can
# successfully be looked up, DNS will be used for hostname resolution
# instead of editing /etc/hosts
# Defaults to true

# project_tld: ddev.site
# The top-level domain used for project URLs
# The default "ddev.site" allows DNS lookup via a wildcard
# If you prefer you can change this to "ddev.local" to preserve
# pre-v1.9 behavior.

# ngrok_args: --subdomain mysite --auth username:pass
# Provide extra flags to the "ngrok http" command, see
# https://ngrok.com/docs#http or run "ngrok http -h"

# disable_settings_management: false
# If true, ddev will not create CMS-specific settings files like
# Drupal's settings.php/settings.ddev.php or TYPO3's AdditionalSettings.php
# In this case the user must provide all such settings.

# no_project_mount: false
# (Experimental) If true, ddev will not mount the project into the web container;
# the user is responsible for mounting it manually or via a script.
# This is to enable experimentation with alternate file mounting strategies.
# For advanced users only!

# provider: default # Currently either "default" or "pantheon"
#
# Many ddev commands can be extended to run tasks before or after the
# ddev command is executed, for example "post-start", "post-import-db",
# "pre-composer", "post-composer"
# See https://ddev.readthedocs.io/en/stable/users/extending-commands/ for more
# information on the commands that can be extended and the tasks you can define
# for them. Example:
#hooks:
# post-import-db:
#   - exec: drush cr
#   - exec: drush updb

docker-compose.chromedriver.yml

version: '3.6'
services:
  chromedriver:
    container_name: ddev-${DDEV_SITENAME}-chromedriver
    image: drupalci/chromedriver:production
    labels:
    # These labels ensure this service is discoverable by ddev
      com.ddev.site-name: ${DDEV_SITENAME}
      com.ddev.approot: ${DDEV_APPROOT}
      com.ddev.app-url: ${DDEV_PRIMARY_URL}
    environment:
      - TZ=America/Chicago
  # This links the Chromedriver service to the web service defined
  # in the main docker-compose.yml, allowing applications running
  # in the web service to access the driver at `chromedriver`.
  web:
    links:
      - chromedriver:${DDEV_HOSTNAME}
    environment:
      # *** One of these must be uncommented ***
      # In order for the system to work, one of these must be uncommented so
      # that the test system can connect to the database.
      # - SIMPLETEST_DB=sqlite://tmp/test.sqlite
      - SIMPLETEST_DB=mysql://db:db@db:3306/db
      #
      # Note: Do not modify the base URL value.
      #      - SIMPLETEST_BASE_URL=http://web
      - SIMPLETEST_BASE_URL=http://ddev-${DDEV_SITENAME}-web
      - BROWSERTEST_OUTPUT_DIRECTORY=/tmp
      - BROWSERTEST_OUTPUT_BASE_URL=${DDEV_PRIMARY_URL}
      - MINK_DRIVER_ARGS_WEBDRIVER=["chrome", {"browserName":"chrome","chromeOptions":{"args":["--disable-gpu","--headless", "--no-sandbox"]}}, "http://chromedriver:9515"]

Started with this repo: https://github.com/WidgetsBurritos/drupal-test-writing