GridBagConstraints are not parsed

[WolfgangHG]

I have this code snippet (originally old code, created without a GUI designer) where the GridBagConstraints are not properly parsed by WindowBuilder:

public MainFrame3()
{
  ...
  
  contentPane = new JPanel();
  contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
  setContentPane(contentPane);
  
  GridBagLayout layout = new GridBagLayout();
  contentPane.setLayout(layout);
  
  ...
  
  JButton btnNewButton = new JButton("New button");
  layout.setConstraints(btnNewButton, new GridBagConstraints(1, 0, 1, 1, 1.0, 0, GridBagConstraints.WEST,
      GridBagConstraints.HORIZONTAL, new Insets(10, 0, 0, 10), 0, 0));
  contentPane.add(btnNewButton);
}

The GridBagConstraints properties don't show the correct ANCHOR, FILL and WEIGTHX values and the button is not rendered properly in preview:

Attached is a full sample project - open "MainFrame3.java" in designer:

WindowBuilderSample.zip