document testcontainers requirement

docs/BROWSER.md

@@ -69,6 +69,8 @@ If the host running maven is different to the host running Selenium (e.g. `remot
 If this is the case you can specify the address to use using:
     `SELENIUM_PROXY_HOSTNAME=ip.address.of.host mvn install`
 **Important**: this could exposed the proxy wider beyond your machine and expose other internal services, so this should only be used on private or internal networks to prevent any information leak.
+The same issue will also impact any other containers started that the tests that the Browser (rather than Jenkins) needs to access.
+For TestContainers you can additionally set `TESTCONTAINERS_HOST_OVERRIDE=ip.address.of.host`
 
 ## Avoid focus steal with Xvnc on Linux
 If you select a real GUI browser, such as Firefox,

docs/DOCKER.md

@@ -71,3 +71,10 @@ It's best explained with an example:
 # Using a custom docker network
 
 If you are using a custom network for the container that executes the testing you may instruct the docker-fixtures to use the same one by setting the env variable `DOCKER_FIXTURES_NETWORK`to specify the network you want your fixtures to connect to. 
+
+# Using TestContainers with a remote webdriver
+
+If you are using a containerized webdriver (or any other remote webdriver) then any containers launched will not be reachable from the remote web browser.
+This will be an issue for some tests that require the browser interact with the container (e.g. for authentication).
+If this is the case then the `TESTCONTAINERS_HOST_OVERRIDE` should be set to `host.docker.internal` or if the remote browser is non local the IP adddress of your machine.
+

vars.cmd

@@ -23,6 +23,7 @@ IF NOT DEFINED IP (
 
 @echo on
 set SELENIUM_PROXY_HOSTNAME=%IP%
+set TESTCONTAINERS_HOST_OVERRIDE=%IP%
 set JENKINS_LOCAL_HOSTNAME=%IP%
 @echo.
 @echo To start the remote firefox container run the following command: