Cannot correctly set selectedIndex of picker when the list contains duplicate items[Bug]

[Enigma86d]

Description

I create a Xamarin Forms project for Android and I write a picker in xaml.
In the xaml file I also write a few items in the ItemsSource, making sure that there are at least two duplicate items.
In the c file I try to set the selectedIndex to the index of the second duplicate item.
The index will be wrongly set to the first duplicate item (not the second one).
Microsoft documentation does not say that picker has to have unique items
https://docs.microsoft.com/en-us/xamarin/xamarin-forms/user-interface/picker/

Steps to Reproduce

1. Create Xamarin project for mobile phones
2. Set Android as the starting project
3. In xaml write a picker that has at least tow duplicate items
4. in c file try to set the selectedIndex to the second duplicate item

    <StackLayout>
        <Picker x:Name="picker"
        Title="Select a monkey"
        TitleColor="Red">
            <Picker.ItemsSource>
                <x:Array Type="{x:Type x:String}">
                    <x:String>Baboon</x:String>
                    <x:String>Capuchin Monkey</x:String>
                    <x:String>Blue Monkey</x:String>
                    <x:String>Squirrel Monkey</x:String>
                    <x:String>Golden Lion Tamarin</x:String>
                    <x:String>Howler Monkey</x:String>
                    <x:String>Capuchin Monkey</x:String>
                    <x:String>Japanese Macaque</x:String>
                </x:Array>
            </Picker.ItemsSource>
        </Picker>
    </StackLayout>

        protected override void OnAppearing()
        {
            base.OnAppearing();
            picker.SelectedIndex = 6;
            int a = picker.SelectedIndex; //a will be equal with 1 instead of 6
        }

Expected Behavior

the selectedIndex to be set to the correct item

Actual Behavior

the selectedIndex is set to the first duplicate item, not the requested item

Basic Information

• Version with issue:
• Last known good version:
• Platform Target Frameworks:
  • Android: 11.0 (R)
• Android Support Library / AndroidX Version:
• NuGet Packages: Xamarin Forms 5.0.0.2337 and Xamarin Essentials 1.7.1 (latest at this time)
• Affected Devices: Android

Environment

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Microsoft Visual Studio Community 2019
Version 16.11.7
VisualStudio.16.Release/16.11.7+31911.196
Microsoft .NET Framework
Version 4.8.03752

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