find a workaround for Help menu bug on macOS (fixes #638)

Author: benfry

app/src/processing/app/ui/Editor.java

@@ -633,7 +633,19 @@ protected void buildMenuBar() {
     base.populateToolsMenu(toolsMenu);
     menubar.add(toolsMenu);
 
-    menubar.add(buildHelpMenu());
+    JMenu helpMenu = buildHelpMenu();
+    if (Platform.isMacOS()) {
+      // There's a bug on macOS since at least 2016 that leaves the
+      // Help menu disabled after a modal dialog has been shown.
+      // In 2018, it was closed by Oracle with a claim that it couldn't
+      // be reproduced: https://bugs.openjdk.org/browse/JDK-8196655
+      // The workaround is to add a space to the end of the menu name,
+      // which disables whatever macOS behavior is causing the problem.
+      // https://github.com/processing/processing4/issues/638
+      helpMenu.setText(helpMenu.getText() + " ");
+    }
+    menubar.add(helpMenu);
+
     Toolkit.setMenuMnemonics(menubar);
     setJMenuBar(menubar);
   }

todo.txt

@@ -1,5 +1,7 @@
 1290 (4.1.2?)
-
+X Help Menu disabled on OS X (looks like a JVM bug)
+X   https://github.com/processing/processing/issues/4353#issuecomment-237715947
+X   https://github.com/processing/processing4/issues/617
 
 contributed
 X “Cannot find a class or type named ‘PApplet’” error
@@ -825,9 +827,6 @@ _   https://github.com/processing/processing4/issues/234
 _   we're not posting any, can we suppress the "allow notifications" message?
 _   https://developer.apple.com/documentation/usernotifications
 _   https://developer.apple.com/documentation/usernotifications/asking_permission_to_use_notifications
-_ Help Menu disabled on OS X (looks like a JVM bug)
-_   https://github.com/processing/processing/issues/4353#issuecomment-237715947
-_   still broken in 11.0.8
 _ Java bug prevents us from setting the dock name of a sketch run from the PDE
 _   https://github.com/processing/processing/issues/5045
 _ client properties