Yangman - Json - no Received data code mirror displayed after running PUT request from form, then selecting GET operation and switching to json

When selecting GET or DELETE operation in form after PUT or POST request is executed and then switching to json, no Received data CM is displayed.
1. Refresh the page. Navigate to network-topology rev. module > config tab > expand network-topology branch > click topology

.
2. Switch view to form.
3. Select PUT operation and insert t1 as topology id.
4. Run PUT operation.
5. Select GET or DELETE operation and switch view to json.
BUGGY BEH: Received data CM is not displayed.