title: Hidden field "ufprt" being added to Razor Umbraco Form - Why?
body: <p>I have got a form (below) that is posted to an umbraco surface controller.</p>
  
  <pre><code>@using (Html.BeginUmbracoForm("AddToBasket", "Basket"))
  {
  
  &lt;h1&gt;@Model.productSelectionModel.Product.Title - @Model.productSelectionModel.Product.Price.ToString("C")&lt;/h1&gt;
  
  &lt;ul&gt;
      @foreach (var productOption in Model.productSelectionModel.ProductOptions)
      {
          &lt;li&gt;@productOption.Option.Title&lt;/li&gt;
          @Html.DropDownList(productOption.Option.Id.ToString(), productOption.ValuesInOptions.ToSelectList(f =&gt; f.OptionValue.OptionValue1, 
                                                     f =&gt; f.Id.ToString(), 
                                                     "Select"));                                             
      }
  &lt;/ul&gt;
  
      &lt;input type="submit" value="Add To Basket"&gt;
  }
  </code></pre>
  
  <p>When I look at the HTML rendered for this form it seems to have added a hidden field called ufprt. Does any one know what this is? Why is it being added, I'm not using it any where ( I don't think I am anyway) </p>
  
  <p>Any ideas?</p>
  
  <pre><code>&lt;input name='ufprt' type='hidden' value='6C01896EF3D5F430F9ED041DD2B0D31F89FA969A085C6F4FDEC3C9D4B906846E7AA80041CEA12573E9F58C1740893B770AAE3319FAA8FA35C89A54D301CFE31B85ADC0D3D9506D208DB068D1257C5F0D5F1B3B90FD59A5C2938EED0A2EB1168AD4573CD5D043D47A8F1AA789E988CC614686B89BE57D35DA8EAAA110044C393F' /&gt;
  </code></pre>