MatCheckbox Indeterminate state doesn't change

[mbaleczny]

Once a state of an indeterminate checkbox is set to null then it's re-rendered correctly. But from state null to true or false it stays the same. Please observe this behaviour below.

Is it a bug or is my approach incorrect?

Code snippet:

@page "/test"

<div class="container">
    <div class="row">
        <div class="col-sm-2">
            <MatCheckbox
                Value="@AllSelected"
                ValueChanged="@((bool? s) => OnChangeAllSelected(s))"
                ValueExpression="@(() => AllSelected)"
                Indeterminate="true">
                <h4>Group</h4>
            </MatCheckbox>
        </div>
        @foreach (var element in _selectElements)
        {
            <div class="col-sm-2">
                <MatCheckbox
                    Value="@element.Selected"
                    ValueChanged="@((bool value) => OnValueChanged(element, value))"
                    ValueExpression="@(() => element.Selected)"
                    Label="@element.Name">
                </MatCheckbox>
            </div>
        }
    </div>
</div>

@code
{
    private readonly List<SelectableElement> _selectElements = new List<SelectableElement>();

    bool? AllSelected { get; set; }

    protected override Task OnInitializedAsync()
    {
        _selectElements.Add(new SelectableElement(false, "1"));
        _selectElements.Add(new SelectableElement(false, "2"));
        _selectElements.Add(new SelectableElement(false, "3"));

        AllSelected = _selectElements.All(element => element.Selected);

        return Task.CompletedTask;
    }

    void OnChangeAllSelected(bool? s)
    {
        AllSelected = s;
        if (AllSelected == null) return;
        
        foreach (var element in _selectElements)
        {
            element.Selected = AllSelected == true;
        }
    }

    Task OnValueChanged(SelectableElement element, bool s)
    {
        element.Selected = s;

        var all = _selectElements.All(r => r.Selected);
        var any = all || _selectElements.Any(r => r.Selected);

        if (any && !all)
        {
            AllSelected = null;
        }
        else
        {
            AllSelected = all;
        }
        
        return Task.CompletedTask;
    }

    class SelectableElement
    {
        public bool Selected { get; set; }

        public string Name { get; }

        public SelectableElement(bool selected, string name)
        {
            Selected = selected;
            Name = name;
        }
    }

}

[tsmeets2]

This bug is still present in MatBlazor 2.6.0