"Error: Property [ORGANIZER] must be specified once" when exporting offline calendars from Etar

[tomgagdotnet]

Hello, as from title, I started receiving this message when exporting anyone of my offline calendars to file. This is new for me, last time I checked it was roughly 2 months ago.

[ford--prefect]

I have the same issue, but the property missing here is [UID].

EDIT: Solved with an older version, v54 worked for me (on an ancient Android, though). Old APK found at izzysoft.de