The previously configured ChromeDriver service is still running / Running Webdriver tests with Grunt
One possible solution is to run your sessions in isolated environments (for example in Docker containers). However trying to achieve this with standard Selenium is complicated - you have to manually start and stop containers or use an infrastructure automation tool like Ansible. Here is where a new Selenium-compatible tool called Selenoid comes into play. Just request two separate sessions in your test and they will run in parallel inside Docker containers. This gives you a lot of flexibility. My talk about it: https://www.youtube.com/watch?v=TGjpc32my0Y