No option for email alerts with google calendar in Thunderbird

After upgrading from Mint 21.3 to 22.3, Thunderbird no longer offers me the option of setting email alerts for events. Details: - I have Provider for Google Calendar installed - I've tried adding my calendar as "Google calendar" and "On the network" but neither offers email alerts. (On the network works better for responding to invitations.) My current work-around is to go to the google calendar app on my phone and set an email alert after creating the event in Thunderbird. That works but is a pain. This worked before. I suspect it's more a configuration issue and less a Mint version issue.