OJS should handle the orphaned notification gracefully. It should either skip rendering the invalid notification or display a placeholder title (e.g., "-") without causing the application to crash.
Due to a hardware failure I have to replace one of my firewalls. OPNsense version still 24.1.10_8 aka 11.2, I made a fresh install from USB, set LAN and WAN so I could update to 24.1.10_8, installed ...