Forms Previewer and ImageResourceExtension not loading

Hi, the forms previewer don't show image from my imageresource, is there something I do wrong? It work well on my Android or iOS

my xaml (The normal ContentPage with:)

<Image Source="{local:ImageResource SIV_Lite.back_menu_haut.png}" />

the class:

[ContentProperty("Source")]
public class ImageResourceExtension : IMarkupExtension
{
public string Source { get; set; }

public object ProvideValue(IServiceProvider serviceProvider)
{
    if (Source == null)
    {
        return null;
    }
    // Do your translation lookup here, using whatever method you require
    var imageSource = ImageSource.FromResource(Source);

    return imageSource;
}

}