title: Dropdown lists don't work correctly with Modal Popup Extenders in newer version of Firefox
body: <p>I recently updated firefox to the latest version, 40.0.2, and have come across a problem dealing with the AJAX ModalPopupExtender and dropdown lists.</p>
  
  <p>The issue is that when I open a ModalPopupExtender and try to select one of the values from the dropdown list, it does nothing.  It keeps the dropdown list open an nothing gets selected.  Furthermore, if I click and hold, it allows me to drag the Popup as if I was dragging the header.</p>
  
  <p>My popups are in the following format:</p>
  
  <pre><code>   &lt;ajax:ModalPopupExtender id="mpeModal" runat="server" PopupControlId="pnlModal" PopupDragHandleControlID="pnlModalHeader" /&gt;
     &lt;asp:Panel id="pnlModal" runat="server" CssClass="modal-panel" style="display:none"&gt;
          &lt;asp:Panel id="pnlModalHeader" runat="server"&gt;
              &lt;uc:PopupHeader id="phModalHeader" Text="Header Text" runat="server /&gt;
          &lt;/asp:Panel&gt;
          &lt;div class="modal-content"&gt;
              &lt;asp:TextBox id="txtField" runat="server" /&gt;
              &lt;asp:DropdownList id="ddlField" runat="server /&gt;
          &lt;/div&gt;
      &lt;/asp:Panel&gt;
  </code></pre>
  
  <p>The last version of Firefox I was using was 34, so I'm not sure if a version between 34 and 40 would have changed how this works.</p>
  
  <p>Any idea what would cause this issue with Dropdown Lists in AJAX Modal Popups?</p>