The following headful system test fails intermittently on Linux. We see this failure quite often in our automated test runs.

ContextMenuNPETest > testContextMenuNPE FAILED
    java.lang.AssertionError: Timeout: Failed to hide context menu.
        at org.junit.Assert.fail(Assert.java:89)
        at org.junit.Assert.assertTrue(Assert.java:42)
        at test.util.Util.waitForLatch(Util.java:400)
        at test.robot.javafx.scene.ContextMenuNPETest.selectSubmenuItem(ContextMenuNPETest.java:105)
        at test.robot.javafx.scene.ContextMenuNPETest.testContextMenuNPE(ContextMenuNPETest.java:111)