When trying to open Multiple instances of Safari for example in test cases when trying to open new window selenium is giving SessionNotCreatedException-
org.openqa.selenium.SessionNotCreatedException: Could not create a session: The Safari instance is already paired with another WebDriver session.
Build info: version: '3.4.0', revision: 'unknown', time: 'unknown'
It seems like it is not supported at the moment.
https://github.com/seleniumhq/selenium-google-code-issue-archive/issues/7042