title: MS Edge: form submitted even if return false
body: <p>I got a strange problem when creating a login form for a website I create for work. I know it has been posed a million times but my case only breaks in Edge.</p>
  
  <p>Principle is: I have a form with username and password. When submitting the form user and pass is validated and logged in in ajax (and returns error if so). If valid it redirects to the main user. (simple, no?)</p>
  
  <p>Problem is that the page is refreshed anyway even if the form have <code>return: false</code>, <strong>but only in Microsoft Edge</strong>. It works on Chrome, IE (even in document mode 10) and Firefox with no problems.</p>
  
  <p>Code in action:</p>
  
  <pre><code>&lt;!-- jQuery + validate plugins are already loaded --&gt;  
  &lt;form id="loginform" method="post" class=""&gt;
      &lt;div class="navbar-login panel"&gt;
          &lt;div class="panel-heading"&gt;
              &lt;h4 class="panel-title"&gt;Connexion au cours&lt;/h4&gt;
          &lt;/div&gt;
  
          &lt;div class="panel-body"&gt;
              &lt;div id="login-warning"&gt;&lt;/div&gt;
              &lt;div class="form-group col-md-12"&gt;
                  &lt;input class="form-control" style="width: 100%;" placeholder="Adresse email" name="LOGIN_EMAIL" type="email"&gt;
              &lt;/div&gt;
              &lt;div class="form-group col-md-12"&gt;
                  &lt;input class="form-control" style="width: 100%;" placeholder="Mot de passe" name="LOGIN_PASSWORD" type="password"&gt;                      
              &lt;/div&gt;
  
          &lt;/div&gt;
          &lt;div class="panel-heading text-right" style="display: table;width: 100%;"&gt;
              &lt;button type="submit" style="float: right;display: inline-block;" class="btn btn-info"&gt;Connexion&lt;/button&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>JS:</p>
  
  <pre><code>$("#loginform").validate({
      debug: false,
      rules: {
          LOGIN_EMAIL: {
              required: true,
              email: true
          },
          LOGIN_PASSWORD: {
              minlength: 6
          }
      }
  });
  $("#loginform").submit(function(e){
      var f = $(this);
      if(f.valid()){
          $.ajax({
              url: "req/ajx_login.php",
              type:"POST",
              cache: false,
              async: false,
              data: f.serialize(),
              success: function(data, status, xhr){
                  // data is "success" if successed, anything else if failed
                  if(data == "success"){
                      location = "/cours";
                  }else{
                      $("#login-warning").html(data);
                  }
              }
          });
      }
      return false;
  });
  </code></pre>
  
  <p>Can someone help? Thanks for future answers.</p>