Zabbix wipes out Applications for non-discoverable anymore items despite 30 days left before item removal

Steps to reproduce:

1. After items not present in latest received JSON for discovery rule zabbix shows informational message like this: "The item is not discovered anymore and will be deleted in 27d 3h 11m (on 2019-11-21 at 15:57)."
2. Configured triggers for this item will still work until the item is deleted after specified period.
3. This means item functionality should remain working until the non-discoverable estimated left time has passed.
4. I have discovered that Zabbix wipes out Applications for these items?
5. Why it does so? This breaks the functionality, because many apps rely on Applications.
6. For example Grafana dashboards will not show these items in dashboards, because applications were wiped out.

1. Navigate to screen title...
2. Click on screen element...
3. ...

Result:
See screenshot...
See log file...
See memory dump...
Expected:

Items should remain functional (because triggers continue to work, hence should also Applications.)

See screenshot....
See attached patch file...