TIme Machine SOMETIMES can't restore individual emails
Have recently encountered, when trying to restore from TimeMachine, that some Macs running Catalina/BigSur/Monterey that CAN restore individual Contacts & Emails, and some CAN'T. Wondering what the difference is.
Typically, one would bring the Mail Viewer window to the foreground and then Enter Time Machine and then see the date timeline on the right. On the "CAN'T' Macs when doing this, the Enter TM step instead switches out the Mail Viewer window for a Finder folder window that then goes back into time. And it seems on Macs where individual emails can't be restore, it applies to individual Contacts as well.
What would cause a difference in the way TimeMachine behaves?