Not sure if this is a Thunderbird problem or calendar problem, but the calendar is not appearing in Thunderbird today. I tried disabling the extension, restarting TB, enabling the extension and restarting TB, but to no avail. I also checked for updates to the calendar and as far as I can tell, it is the current version (Provider for Google Calendar 3.3 is the extension). The problem began today.
TB: 52.6.0
Thanks for any advice.