When I search for events in Calendar.app in only finds events created after I installed Sonoma. This feels very much like a cache issue. When I, a couple of times, have had similar problems in the past, the solution has been to delete the cache of iCal/Calender.app (a couple of cache-files in ~/Library/Calendars) but when I look there now there are no longer any cache-files or -folders in that directory. And all results on Google refers to that directory.
Where is the cache for Calendar.app in Sonoma? How do I fix that I can't search for old events in Calendar.app?