Use Popup.back() instead of Popup.close() to get no conflicts if a Popup is opened as "Sub Popup"

- .back() is also .close() if there is no "popup layer" left

client/components/rules/triggers/boardTriggers.js

@@ -116,6 +116,6 @@ Template.boardCardTitlePopup.events({
       .trim();
     Popup.getOpenerComponent().setNameFilter(title);
     event.preventDefault();
-    Popup.close();
+    Popup.back();
   },
 });