A DESCRIPTION OF THE PROBLEM :
Until Java 8 and JavaFX 8 the TextFieldSkin provided the ability to add custom MenuItems to the default ContextMenu by overriding the Method "public void populateContextMenu(final ContextMenu pContextMenu)".

With the refactoring for JPMS Modules this method went into the TextInputControlBehavior which is not public API.

So currently there is no way to append MenuItems to the ContextMenu. I would like to propose an Enhancement to get this API back into the public API of JavaFX.