clear previous comment dialog before opening

CHANGELOG

+minerva (12.3.0~alpha.0) unstable; urgency=low
+  * Feature: added current username next to logout button in admin panel
+  * Improvement: New comment dialog does not contain content of previous comment dialog
+
 minerva (12.2.0~beta.0) unstable; urgency=medium
   * Feature: bug report utility
   * Small improvement: JS plugin can create listener that is triggered on

frontend-js/src/main/js/gui/CommentDialog.js

@@ -85,8 +85,9 @@ CommentDialog.prototype.open = function (identifiedElements) {
       self.setEmail(user.getEmail());
       self.setName(user.getName() + " " + user.getSurname());
     }
-
-    $(self.getElement()).dialog("open");
+    var dialog = $(self.getElement());
+    dialog.find('textarea').val('');
+    dialog.dialog("open");
   });
 };