* Expose `DefaultApplicationMenu`.
Add `FindByLabel` and `ItemAt` for finding menu items in a menu
* Add `Menu.RemoveMenuItem()`, `MneuItem.GetAccelerator()` and `MenuItem.RemoveAccelerator()`
* Remove `Update`
* Iterate when removing menu items
* Add `GetSubmenu()`
Introduced the ability to clone a menu, along with its submenus, in Linux-based web applications to create a full deep copy. This fixes reusing the application menu for window menus.