Version 4.2.3.3 * [CardDAV] roll back commons-io to 2.8.0 for API levels <26 (fixes contacts sync problem on Android <8) * [CalDAV] EventValidator: fix problem where COUNT=-1 was mistakenly added when an invalid RRULE was repaired * [CalDAV] EventValidator: always set UNTIL of repaired RRULEs in UTC (may fix missed occurrences) * [CalDAV] generate random filename if UID can't be used as file name (fixes rare problem when .ics files are imported from Web site and then synced)