JFrame does not paint content in XVFB / X11vnc environment

ADDITIONAL SYSTEM INFORMATION :
Ubuntu Server with openssh, xvfb, x11vnc, Eclipse 2018-12, Java Version 11.0.1

A DESCRIPTION OF THE PROBLEM :
JFrames have no content in an XVFB / x11vnc environment with java 11. They open up and can be moved around, but they do not paint the content. The sample provided worked with a java 8 environment.

REGRESSION : Last worked in version 8u181

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
 * Set up VM with above config, or use the container from: https://hub.docker.com/r/inetsoftware/ubuntu-x11-eclipse/
 * Create a new Java Project with provided source code
 * Download 11.0.1 JDK and set up as run configuration
 * Run the Example


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
A Frame with the Text "tada" should open
ACTUAL -
An empty frame opens

---------- BEGIN SOURCE ----------
import javax.swing.JFrame;
import javax.swing.JLabel;

public class FrameCheck {

public static void main(String[] args) {
JFrame frame = new JFrame("FrameCheck");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.getContentPane().add(new JLabel("tada"));
frame.setVisible(true);
}

}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
There is no workaround. Running the code with java 8 works as expected

FREQUENCY : always