[Bug]: ReactiveUI.Maui nested ReactiveContentView does not deactivate

[loupceuxl2]

Describe the bug 🐞

In Maui a ReactiveContentView [Child] nested inside a ReactiveContentPage [Parent] does not get deactivated (even if I explicity call Activator.Deactivate on the Child view model from inside the Parent view model). This applies only to the Child view. Oddly enough the Child view model does deactivate. Both the view and view model for the Parent do get deactivated properly. I'm using Splat to register (Locator.CurrentMutable.Register). I've tried both ViewModelViewHost and injecting the RCV in directly. Resolving View to ViewModels works fine.

Step to reproduce

# Parent page: I'm inside a ReactiveTabbedPage
<rxui:ReactiveContentPage 
                          xmlns:v="clr-namespace:Assembly.Views" 
                          xmlns:vm="clr-namespace:Assembly.ViewModels"
                          x:DataType="vm:ParentViewModel"
                          x:TypeArguments="vm:ParentViewModel"
                          x:Class="NQXMaui.Views.ParentPage"
                          BindingContext="vm:ParentViewModel">
    <rxui:ReactiveContentPage.Content>
        <ScrollView>
            <VerticalStackLayout>
                <v:Child x:Name="Child"></v:Child><!-- Method 1-->
                <!--<rxui:ViewModelViewHost x:Name="ChildViewModelViewHost"></rxui:ViewModelViewHost>--><!-- Method 2-->
            </VerticalStackLayout>
        </ScrollView>
    </rxui:ReactiveContentPage.Content>
</rxui:ReactiveContentPage>

# Parent code-behind
public partial class ParentPage
{
	public ParentPage()
	{
		InitializeComponent();

		//BindingContext = ViewModel;
		
		this.WhenActivated(disposables =>
		{
            // Method 1
            this.OneWayBind(ViewModel,
					vm => vm.ChildViewModel,
					v => v.Child.ViewModel)
				.DisposeWith(disposables);

            // Method 2
            /*
            this.OneWayBind(ViewModel,
                    vm => vm.ChildViewModel,
                    v => v.ChildViewModelViewHost.ViewModel)
                .DisposeWith(disposables);
            */

            // Always gets called switching between tabs.
			Disposable
				.Create(() => Debug.WriteLine($"Deactivating: {nameof(ParentPage)}"))
				.DisposeWith(disposables);
		});
	}
}

# Parent VM
public class ParentViewModel : ReactiveObject, IActivatableViewModel
{
    public ViewModelActivator Activator { get; }

    //[Reactive]
    public ChildViewModel ChildViewModel { get; /* private set; */ }

    public ParentViewModel()
    {
        Activator = new ViewModelActivator();
        ChildViewModel = new ChildViewModel();
    }

    this.WhenActivated(disposables =>
    {
        // ChildViewModel.Activator.Activate();
        // Always gets called switching between tabs.
        Disposable
            .Create(() => 
            {
                Debug.WriteLine($"Deactivating: {nameof(ParentViewModel)}")
                // ChildViewModel.Activator.Deactivate()
            })
            .DisposeWith(disposables);
    });
}


# Child
<rxui:ReactiveContentView
             xmlns:vm="clr-namespace:Assembly.ViewModels" 
             x:DataType="vm:ChildViewModel"
             x:TypeArguments="vm:ChildViewModel"
             x:Class="Assembly.ChildView">
    <rxui:ReactiveContentView.Content>
        ...
    </rxui:ReactiveContentView.Content>
</rxui:ReactiveContentView>

# Child code-behind
public partial class ChildView
{
    public ChildView()
    {
        InitializeComponent();

        BindingContext = ViewModel;

        this.WhenActivated(disposables =>
        {
            // Never gets called.
            Disposable.Create(() => Debug.WriteLine($"Deactivating: {nameof(ChildView)}"))
				.DisposeWith(disposables); ;
        });
    }
}

# Child VM
public class ChildViewModel : ReactiveObject, IActivatableViewModel
{
    public ViewModelActivator Activator { get; }

    public ChildViewModel()
    {
        Activator = new ViewModelActivator();

        this.WhenActivated(disposables =>
        {
            // Sometimes gets called depending on method used (see above).
            Disposable.Create(() => Debug.WriteLine($"Deactivating: {nameof(ChildViewModel)}"))
                .DisposeWith(disposables);
        });
    }
}

Reproduction repository

https://github.com/reactiveui/ReactiveUI

Expected behavior

ChildView calls:

            Disposable.Create(() => Debug.WriteLine($"Deactivating: {nameof(ChildView)}"))
				.DisposeWith(disposables); ;

Screenshots 🖼️

No response

IDE

Visual Studio 2022

Operating system

Windows

Version

No response

Device

No response

ReactiveUI Version

ReactiveUI.Maui 18.4.1, 18.4.22 (VS preview release for the latter)

Additional information ℹ️

No response