I understand that alerts/notifications are not syncing between Google Calendar and Mac Calendar . We’re currently on a high case season, so we’re doing everything possible to contact all of our customers. I’m sorry for the long delay and thank you for your patience.
Thank you for sharing this URL
https://support.google.com/calendar/thread/13679079 to understand the issue you're having, there was an investigation with our Engineering and Product Development Team about this specific issue and I have consulted with them about your recent request too.
How to reproduce the issue:
- Add a Google Calendar/CalDAV account to MacOS.
- Open Apple's native calendar app (formerly called iCal)-
- Create an event in Apple Calendar on MacOS and add an alert/reminder/notification (e.g. 5 minutes before event)
- Go to Google Calendar's web interface, the event appears but no notification/alert is set.
The final insights and resolution form our Engineering and Product Development Team are that Google Calendar CalDav implementation supports alarms/notifications (VALARM), but it doesn't support the value AUDIO for the ACTION attribute, which Apple uses to send alerts/notifications about events. Google Calendar supports DISPLAY and EMAIL values only, this is because Google Calendar only have display and email options when setting up an event notification.
Since Google Calendar doesn't strip the VALARM ACTION:AUDIO, other calendar client devices syncing with Google Calendar will still have the VALARM ACTION:AUDIO. In the case of the iOS calendar, presumably they work with VALARM ACTION:AUDIO just like the MacOS client, so the alerts will work on iOS just fine...just not within the Google Calendar web interface or on android.
Google Calendar and our syncing tools allow you to synchronize your events, however, alerts and notifications are cosmetic features included in the products, since Google Calendar and Mac Calendar are two completely different products (internally) they don't use the same language for specific features. This is something that has been escalated to both Product Teams, Google and Apple, currently there is no estimated time to know if this is going to be fix by both products to integrate the same internal language for alerts and notifications. We encourage you to keep using Google Products, and for your iOS devices, to download the Google Calendar app from your Apple Store.