Searchbar by correcting one character in the middle, cursor goes to the last character

I have a few problems with the SearchBar under Android.

I typed a word and then I want to change something in the middle of the word. After change only one character the cursor goes to the last place and type after the last character the changes you made.

I made a little sample app and there is the problem too.

public App()
        {
            searchbar = new SearchBar();
            var button = new Button {
                Text = "Focus searchbar",
            };
            button.Clicked += (sender, e) => {
                searchbar.Focus();
            };
            // The root page of your application
            MainPage = new ContentPage {
                Content = new StackLayout {
                    VerticalOptions = LayoutOptions.Center,
                    Children = {
                        new Label {
                            XAlign = TextAlignment.Center,
                            Text = "Welcome to Xamarin Forms!"
                        }, 
                        searchbar,
                        button
                    }
                }
            };
        }

EDIT: I opened a bug report

https://bugzilla.xamarin.com/show_bug.cgi?id=28969