[remote] Error: TypeError: idn_to_ascii() expects parameter 1 to be string, null given at <<closure>>

[Githopp192]

Steps to reproduce

1. Create Calendar entry
2. Entry will not shown; need to logoff; then entry is there
3. Entry did not save properly; some changes - like chaning the Calender Sharing option will not be saved anymore.
4. After logout/login again, the entry was "not confirmed" .. but it was confirmed before
5. This behave is the same or similar with different Browsers (Chrome/Edge) ..

I never saw such a behave from this app; since i did the upgrade just some minutes ago to Version: 1.6.5, the behaviour of this app changed completely

Expected behaviour

All those things obove should not happen

Actual behaviour

see obove

Server configuration