Main: adapted menu to macOS style.

src/main/java/es/kauron/jstudy/controller/Controller.java

@@ -16,6 +16,8 @@ import javafx.fxml.FXML;
 import javafx.fxml.FXMLLoader;
 import javafx.fxml.Initializable;
 import javafx.scene.Parent;
+import javafx.scene.control.Menu;
+import javafx.scene.control.MenuBar;
 import javafx.scene.control.MenuItem;
 import javafx.scene.control.*;
 import javafx.scene.image.Image;
@@ -54,6 +56,9 @@ public class Controller implements Initializable {
     @FXML
     private MenuItem menuCloseTab, menuSave, menuUndo, menuRedo;
 
+    @FXML
+    private MenuBar menuBar;
+
     private final BooleanProperty tabIsTable = new SimpleBooleanProperty(false);
     private final Map<Tab, Initializable> tabMap = new HashMap<>();
     private String updateURL, updateFileName;
@@ -96,9 +101,26 @@ public class Controller implements Initializable {
                 }
             })
         );
+        // Do not show icons in the menu items of the main menu in macOS.
+        Platform.runLater(() -> {
+            if (System.getProperty("os.name").toLowerCase().startsWith("mac os x"))
+                for (Menu m : menuBar.getMenus())
+                    removeIcon(m);
+        });
         new Thread(this::checkUpdate).start();
     }
 
+    private void removeIcon(Menu menu) {
+        menu.setGraphic(null);
+        for (MenuItem item : menu.getItems()) {
+            if (item instanceof Menu) {
+                removeIcon((Menu) item);
+            } else {
+                item.setGraphic(null);
+            }
+        }
+    }
+
     private boolean isTableTab(Tab tab) {
         return tabMap.containsKey(tab) && tabMap.get(tab) instanceof TableController;
     }

src/main/resources/es/kauron/jstudy/view/main.fxml

@@ -86,7 +86,7 @@
     </TabPane>
   </center>
   <top>
-    <MenuBar>
+    <MenuBar fx:id="menuBar" useSystemMenuBar="true">
       <menus>
         <Menu text="_File">
           <items>