I was looking to see how the template binding was done in #4269 and noticed this line of code :
Should this not have been nameof(ItemsSource):
public static readonly BindableProperty ItemsSourceProperty = BindableProperty.Create(nameof(ItemsSource), typeof(IEnumerable), typeof(Map), default(IEnumerable),
@djcparker Thanks for reporting this, see #5499
Fixed!
(not merged yet, reopening 馃槃 )
closed by #5499