RadzenDropDownDataGrid: LoadData deadlock for async database-calls

I have this simple RadzenDropDown where the user can type a city-name and it will autocomplete what matches in the database.

  <RadzenDropDown AllowFiltering="true"                            
                        @* Count="_totalMatches" *@
                        Data="@_cities"
                        FilterDelay="300"
                        LoadData="HandleLoadDataAsync"
                        Placeholder="@(Localizer["Type the name of the city ..."])"
                        TValue="City"
                        ValueChanged="HandleValueChangedAsync">
    <Template>
        @((context as City)?.FormattedCityName)
    </Template>
</RadzenDropDown>

@code {
    [Parameter]
    public EventCallback<City> OnSelectedItemChange { get; set; }

    IEnumerable<City> _cities;

    private async Task HandleLoadDataAsync(LoadDataArgs loadData)
    {
       _cities = await DbContext.City.Where(...).OrderBy(...).Select(...).ToListAsync();

        await InvokeAsync(StateHasChanged);
    }

    private async Task HandleValueChangedAsync(TblCity city)
    {
        await OnSelectedItemChange.InvokeAsync(city);
    }
}

which all is working as expected. However, if I change to RadzenDropDownDataGrid and un-commenting (and setting) the Count-property I got a deadlock when HandleLoadDataAsync is invoked. I can see, that the SQL-is generated but it never goes further than the await ... ToListAsync() call.

First I thought this is an issue with the DbContext but I tried calling await DbContext...ToListAsync() in the OnInitializedAsync lifecycle-call which worked as expected. So I guess it has something to to with how the LoadData event-callback is invoked? Just guessing here as I wonder why it is working for RadzenDropDown but not for RadzenDropDownDataGrid.

Side note: Using the non-async calls will work but I still guess this is an issue/bug?

I'm unable to reproduce such exception. If you have Radzen subscription you can send us an repro application at info@radzen.com to debug it.

I ran into the same issue, was able to reproduce it by modifying the demo at:

radzen-blazor-master/RadzenBlazorDemos/Pages/DropDownDataGridPage.razor

Simply change the declaration of the LoadData() function to be async and add any async await to the first line:

    async Task LoadData(LoadDataArgs args)
    {
        await Task.Delay(100);

        var query = dbContext.Customers.AsQueryable();

When running the page, open the Custom filtering example dropdown and input any filter text, the filtering will not apply and elements on the page will stop responding.