Blazor Page (WebAssembly/WASM): How can EditForm and EditContext are always be null in SetParametersAsync?

Question

I have a blazor page with the below markup. I am trying to add custom validation to it, which requires the EditContext.

My page (abbrievated) is as below:

<AuthorizeView>
<Authorized Context="Auth">
    @if (_part == null)
    {
        <div>Loading...</div>
    }
    else
    {
<EditForm Model="@_part" OnValidSubmit="@HandleValidSubmit">
              ....
</EditForm>

I have in my "code":

    [CascadingParameter]
    private EditContext EditContext { get; set; }
    [CascadingParameter]
    private EditForm EditForm { get; set; }

And ...

    protected override void OnParametersSet()
    {
        base.OnParametersSet();

        Debugger.Break();


        if (this.EditContext != null)
        {
            this.FieldIdentifier = this.EditContext.Field("Sku");
        }
        else
        {
            if (this.EditForm != null)
            {
                this.EditContext = this.EditForm.EditContext;
            }
        }
    }

In OnParametersSet, EditContext and EditForm are always null. Everything else seems to be fine. How could they be null?