[libical] TZID on DATE-TIME value can override time specified in UTC
Good morning, I've noticed that recurring events which have been sent by third parties cannot be removed singularly. For example an event recurring everyday at 9AM from Monday to Friday accepted via a common email invitation: if I want to remove the recurrence of Tuesday only it will NOT get removed.
Same problem for CalDav local sync: if a recurrent event has been added by another client and it's synced in Evolution, a single recurrence cannot be removed in Evolution. If gets removed from another client doesn't get removed in Evolution either but it does on the other clients (tested along with Kronolith [Horde calendar] and Thunderbird).
A single occurrence of a recurrent event appears to be removable on Evolution only if the recurrent event has been created on the local Evolution calendar.
Extensively tested on Evolution 3.26.6 (3.26.6-1.fc27) (Fedora release 27). Evolution 3.24.2 (on FreeBSD 11.1-RELEASE) was NOT affected by this bug until I've accepted a meeting from an iCal (sent from the Evolution from Linux) and then same issue started affecting both CalDav local "replica" and local calendar. Removing the imported meeting sent everything back to normal.