Issue #1592688 by jgtrescazes, tstoeckler, eric.chenchao, fietserwin, Heine,...

Issue #1592688 by jgtrescazes, tstoeckler, eric.chenchao, fietserwin, Heine, stefan.r, Dmitriy.trt, lachezar.valchev, bogdan khrupa: #states can cause the form "required" mark to appear more than once on the same element

misc/states.js

@@ -493,7 +493,11 @@ $(document).bind('state:disabled', function(e) {
 $(document).bind('state:required', function(e) {
   if (e.trigger) {
     if (e.value) {
-      $(e.target).closest('.form-item, .form-wrapper').find('label').append('<span class="form-required">*</span>');
+      var $label = $(e.target).closest('.form-item, .form-wrapper').find('label');
+      // Avoids duplicate required markers on initialization.
+      if (!$label.find('.form-required').length) {
+        $label.append('<span class="form-required">*</span>');
+      }
     }
     else {
       $(e.target).closest('.form-item, .form-wrapper').find('label .form-required').remove();