title: HTML 5 validation not working in Firefox with Knockout options binding
body: <p>I am trying to force users to choose an option in a drop down menu, populated by Knockout. I am using the HTML5 "required" validation attribute, and it works fine in Chrome 38, and Opera 25, but it fails in Firefox 33.</p>
  
  <p>Here is my HTML:</p>
  
  <pre><code>&lt;form id="theForm" class="form-horizontal form-validate" action="" method="post"&gt;
      &lt;div class="control-group"&gt;
          &lt;label class="control-label"&gt;To&lt;/label&gt;
          &lt;div class="controls"&gt;
              &lt;select required data-bind="options: listRecipients,
                                      optionsCaption: 'Choose...', 
                                     optionsText: 'name',
                                     value: selectedRecipient"&gt;&lt;/select&gt;
          &lt;/div&gt;
      &lt;/div&gt;
      &lt;button type="submit" class="btn btn-primary"&gt;Submit Changes&lt;/button&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>And the corresponding JavaScript:</p>
  
  <pre><code>$(document).ready(function () {
      function AppViewModel() {
          // KO model
          self.listRecipients = ko.observableArray([{
              name: 'foo',
              id: '1'
          }, {
              name: 'bar',
              id: '2'
          }]);
          self.selectedRecipient = ko.observable();
      }
  
      // Activates knockout.js
      var appViewModel = new AppViewModel();
      ko.applyBindings(appViewModel);
  });
  </code></pre>
  
  <p>Corresponding <a href="http://jsfiddle.net/philcms1/0onuefdg/" rel="nofollow">jsFiddle</a>.</p>
  
  <p>Using jQuery validation with Knockout "options" seems rather complex, and I cannot find much documentation on using knockout-validation with "options" either... any idea why it is not working  in FF?</p>