@Override
	public void propertyChange(PropertyChangeEvent e) {
		Object o = e.getNewValue();
		if (o instanceof JComponent) {
			focusOwner = (JComponent) o;
		}
		else {
			focusOwner = null;
		}
	}
This spacer addresses the optical impression that the message panel changes size when showing details
Ghidra/Framework/Docking/src/main/java/docking/ErrLogExpandableDialog.java