Reports

Turned out to be pretty simple - all I have to do is wrap the offending control in its own Editform:

<EditForm Model="@dummymodel">
    <TelerikComboBox Id="Category-field" Data="@Categories" @bind-Value="@CurrentCategoryId" TextField="@nameof(Category.Name)" ValueField="@nameof(Category.Id)" OnChange="@FilterItems" >
        <ComboBoxSettings>
            <ComboBoxPopupSettings Class="dropdownsize;" />
        </ComboBoxSettings>
    </TelerikComboBox>
</EditForm>

with the dummymodel defined as:

private object dummymodel = new object();

and it works fine...

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