Scenario: Using the Send message dialog on one's course profile
Step: I press "Close"

Failed on nightly.
http://nightly.test.in.moodle.com:8080/job/M.08%20Run%20all%20behat%20features%20in%20firefox-linux/134/console

This is one of those random issues as it passed testing well on MDL-48933 and failed in one case and passed in another.

Reason being: Message window is closed after 2 seconds, and if server is slow, it will not be able to press close button.