Snippet: Disable the Menu Completely
// Disable the header menu.
add_filter( 'totaltheme/header/menu/is_enabled', '__return_false' );
// Optional: Remove any Customizer header menu options.
add_filter( 'totaltheme/header/menu/is_custom', '__return_true' );
All PHP snippets should be added via child theme's functions.php file or via a plugin (we recommend WPCode)