Window.menubar
  The Window.menubar property returns the
  menubar object, whose visibility can be checked.
Syntax
objRef = window.menubar
Example
  The following complete HTML example demonstrates how the visible property
  of the menubar object is used.
<html>
<head>
  <title>Various DOM Tests</title>
  <script>
    var visible = window.menubar.visible;
  </script>
</head>
<body>
  <p>Various DOM Tests</p>
</body>
</html>
Specifications
| Specification | 
|---|
| HTML Standard # dom-window-menubar-dev | 
Browser compatibility
BCD tables only load in the browser