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Shared Google CalendarGoogle Calendar invites
Others get notification emails If added to the event explicitly
Others can edit event Only if event creator checks "Guests can modify event"
Custom colors Per calendar
Each event appears onceNo Event appears both in the shared and in the personal calendar if invited. Removal from personal calendar marks as "No" in shared calendar.
Others get event change notifications If added to the event explicitly
Event creator notified of RSVPs If configured via Reminders & Notifications settings
Inform others of unavailable times Mark block as busy and just don't invite othersNo Unless bogus-inviting others to unavailable times as an event
Retrospective of events together Uncheck other calendars- Search / filtering?
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