title: Modal popup extender its working fine but in my aspx page all button's postback event is not fired
body: <p>linkbutton on which i want to show modal popup extender</p>
  
  <pre><code>    &lt;asp:LinkButton ID="Feedback" runat="server" CssClass="hyperlinkann" OnClientClick="return false;"&gt;Give your feedback&lt;/asp:LinkButton&gt;
  
      &lt;cc1:ModalPopupExtender ID="ModalPopupExtender1" runat="server" TargetControlID="Feedback"
                                                  PopupControlID="popuppanel" BackgroundCssClass="modalBackground" CancelControlID="Cancel"&gt;
                                                  &lt;/cc1:ModalPopupExtender&gt;
  </code></pre>
  
  <p>Here i don't use okcontrlID because i want to do some coding on submit</p>
  
  <pre><code>      &lt;asp:Panel ID="popuppanel" runat="server" CssClass="confirm-dialog" DefaultButton="okbutton"&gt;
  
          &lt;div class="divpopup"&gt;
              &lt;h3 style="color:Black;font-weight:bold;"&gt;Feedback&lt;/h3&gt;
              &lt;asp:TextBox ID="txt_comments" runat="server" TextMode="MultiLine" Width="190" Height="50" placeholder="Give Feedback" required="require"
              BorderColor="Black"&gt;&lt;/asp:TextBox&gt;
  
              &lt;br /&gt;&lt;br /&gt;
             &lt;asp:Button ID="okbutton" runat="server" Text="Submit" CssClass="popupbutton" 
                  onclick="okbutton_Click" /&gt;
              &lt;asp:Button ID="Cancel" runat="server" Text="Cancel" CssClass="popupbutton" /&gt; 
          &lt;/div&gt;
  
       &lt;/asp:Panel&gt;
  </code></pre>