Change Details

Selenium fails to connect to firefox (headless not sauce): `unable to obtain stable firefox connection in 60 seconds` or `Connection refused - connect(2) (Errno::ECONNREFUSED)` Examples: http://raita.wmflabs.org/#projects/https%3A%2F%2Fgithub.com%2Fwmde%2FWikidataBrowserTests.git/builds/lvOxGqnKTwmPAu3ctkIovg http://raita.wmflabs.org/#projects/https%3A%2F%2Fgithub.com%2Fwmde%2FWikidataBrowserTests.git/builds/FLBroL2mRIOCJAGEQ3QFvw (from T116166#1769311 )