With JDK 13.0.1 and a local build of the latest jfx sources, I am seeing the following system test failure on mac in one of the SwingNode tests:

test.javafx.embed.swing.SwingNodeScaleTest > testScale FAILED
    java.lang.AssertionError: expected:<300> but was:<53>
        at org.junit.Assert.fail(Assert.java:91)
        at org.junit.Assert.failNotEquals(Assert.java:645)
        at org.junit.Assert.assertEquals(Assert.java:126)
        at org.junit.Assert.assertEquals(Assert.java:470)
        at org.junit.Assert.assertEquals(Assert.java:454)
        at test.javafx.embed.swing.SwingNodeScaleTest.testScale(SwingNodeScaleTest.java:84)

This started happening recently, but I'm not yet sure whether it was upgrading from JDK 12 to JDK 13.0.1 that triggered the bug or some change in JavaFX.

This is likely to be a product bug rather than a test bug.