Provide an easy way to position the popup in the center of the screen in a MVVM-friendly manner.
Consider the case when the target is a view that carries information about the popup and cannot be the page.
when placement target is a StackLayout/GridLayout the popup is not visualized correctly.
Workaround: set VerticalOptions="StartAndExpand" to the StackLayout
Please add an option to center the Xamarin Popup on the page, both horizontally and vertically. The popup should not move when pickers (and other similar controls) are opened/closed.