NavigationPrecommitHandler Delegate
https://html.spec.whatwg.org/multipage/nav-history-apis.html#navigationprecommithandler
public delegate object? NavigationPrecommitHandler(NavigationPrecommitController controller)https://html.spec.whatwg.org/multipage/nav-history-apis.html#navigationprecommithandler
public delegate object? NavigationPrecommitHandler(NavigationPrecommitController controller)