maui-linux/Xamarin.Forms.Sandbox/MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             x:Class="Xamarin.Forms.Sandbox.MainPage"
             xmlns:ios="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core"
             ios:Page.UseSafeArea="true">
    <ContentPage.Content>
        <StackLayout>
            <Button Text="I am a Button"  />
        </StackLayout>
    </ContentPage.Content>
</ContentPage>