What happened to the "advanced options" then "external calendar"??

This last update vanished the option of selecting "advanced options" then  selecting a different external calendar.  My Zoom account is set up for Google Calendar.  But I would add this additional option, and a iCal option would be selected, so it would add a iCal entity to my Mac Calendar.

Now it vanished?  Any idea where it is or how I can get it back?