Main Menu Extending

  1. In Project panel, Create a script: Assets/Editor/ExtendEditor.js
    // Extend main menu
    // The first parameter defines the path of the menu
    // The second parameter definde the action with the menu is selected
    G.extend.menu('Test/ClickMe', function() {
     alert('Welcome!');
    });
    
  2. Reload web page to check the result:
    Preview

Demo

Extend-menu Demo