ASPxCallbackPanel - If HideContentOnCallback is True and the panel content contains text not wrapped by any tag, this text is not hidden on callback

Hi,

Attached is a screenshot comparing two callbacks. They are both the same calls, however, I believe there is a bug in the ASPxCallbackPanel. It does not hide the content at the first initial call, only after the first call happens and it gets called again.

My code is as follows:

<asp:Panel runat="server" CssClass="panelResult" ID="resultBing" ClientIDMode="Static" style="display: none;">
          <div class="engineLeft">
               <div class="engineLogo"><asp:HyperLink runat="server" ID="linkBing" Target="_blank"><img id="bingLogo" src="Images/Main/Engine_Bing.png" alt="Bing" title="Bing" onmouseover="new Effect.Opacity('bingLogo', { from: 0.2, to: 1 });" onmouseout="new Effect.Opacity('bingLogo', { from: 1, to: 0.2 });" /></asp:HyperLink></div>
            <div id="bingNavigationL" class="navigationLeft" onmouseover="new Effect.Opacity('bingNavigationL', { from: 0.2, to: 1 });" onmouseout="new Effect.Opacity('bingNavigationL', { from: 1, to: 0.2 });"><dx:ASPxImage ID="bingNavigationImageL" ImageUrl="Images/Main/arrowLeft.png" AlternateText="Previous Results" runat="server"><ClientSideEvents Click="function(s, e) { bingImagesCb.PerformCallback('previous'); }" /></dx:ASPxImage></div>
            <div id="bingNavigationR" class="navigationRight" onmouseover="new Effect.Opacity('bingNavigationR', { from: 0.2, to: 1 });" onmouseout="new Effect.Opacity('bingNavigationR', { from: 1, to: 0.2 });"><dx:ASPxImage ID="bingNavigationImageR" ImageUrl="Images/Main/arrowRight.png" AlternateText="Next Results" runat="server"><ClientSideEvents Click="function(s, e) { bingImagesCb.PerformCallback('next'); }" /></dx:ASPxImage></div>
          </div>
          <div class="engineRight">
               <dx:ASPxCallbackPanel ID="bingImages" runat="server" CssClass="engineResult" ClientInstanceName="bingImagesCb" HideContentOnCallback="True" ClientIDMode="Static" oncallback="bingImages_Callback" ViewStateMode="Enabled"></dx:ASPxCallbackPanel>
          </div>
     </asp:Panel>

If you see on the first screenshot, when the first time the callback happens, the loading panel is on the lower side of the div, since the container holding the content is still visible. However, when I do the second callback, it is aligned perfectly, because the callback hides the content div and reactivated it when it goes away.

Do you know why it doesn't do it the first time?

Thanks.