title: scenebuilder 8.4.1: custom font property not visible on custom properties section
body: <p>create a custom component, make it a jar and add it to the scenebuilder libraries so that it is visible => OK
  declare string / float / integer / object properties  etc so that they are visible in scenebuilder => Ok</p>
  
  <p>But I can not declare a property "Font" and be visible in the custom properties of scenebuilder.</p>
  
  <p>I do this in my controller class: </p>
  
  <pre><code>private SimpleObjectProperty&lt;Font&gt; TextFont = new SimpleObjectProperty&lt;&gt;(Font.font("System",FontWeight.NORMAL,12));
  
  public Font getTextFont() {
      return TextFont.get();
  }
  
  public SimpleObjectProperty&lt;Font&gt; textFontProperty() {
      return TextFont;
  }
  
  public void setTextFont(Font textFont) {
      this.TextFont.set(textFont);
         }
  </code></pre>
  
  <p>my other properties appear but not this one.</p>
  
  <p>if anyone has any documentation on it...</p>
  
  <p>thanks in advance</p>