import javafx.application.Application; import javafx.stage.Stage; static bool startJavaFX_firstStart = true; static void startJavaFX(final Class appClass) { thread "Starting JavaFX" { if (startJavaFX_firstStart) { startJavaFX_firstStart = false; fixContextClassLoader(); // Maybe not needed anymore now Application.launch(appClass); } else jfxLater(r { Application app = nuObject(appClass); new Stage stage; app.start(stage); }); } }