It's quite possible that this test causes Firefox (marionette) hang on travis

Author: barancev

java/client/test/org/openqa/selenium/JavascriptEnabledDriverTest.java

@@ -229,6 +229,7 @@ public void testShouldBeAbleToGetTheLocationOfAnElement() {
   @NeedsFreshDriver
   @Test
   @Ignore(value = SAFARI, reason = "issue 3693")
+  @Ignore(value = MARIONETTE, issue = "https://github.com/mozilla/geckodriver/issues/611")
   public void testShouldBeAbleToClickALinkThatClosesAWindow() throws Exception {
     driver.get(pages.javascriptPage);