guest account cannot be removed from admin panel

frontend-js/src/main/js/gui/admin/UsersAdminPanel.js

@@ -252,7 +252,11 @@ UsersAdminPanel.prototype.userToTableRow = function (user, row) {
   row[2] = user.getSurname();
   row[3] = user.getEmail();
   row[4] = "<button name='showEditDialog' data='" + user.getLogin() + "'><i class='fa fa-edit' style='font-size:17px'></i></button>";
-  row[5] = "<button name='removeUser' data='" + user.getLogin() + "'><i class='fa fa-trash-o' style='font-size:17px'></i></button>";
+  var disabled = "";
+  if (user.getLogin() === "anonymous") {
+    disabled = " disabled ";
+  }
+  row[5] = "<button name='removeUser' " + disabled + " data='" + user.getLogin() + "'><i class='fa fa-trash-o' style='font-size:17px'></i></button>";
 
   return row;
 };