No settings for Mail's On My Mac Trash folder?

In macOS Mail, is there no setting to erase deleted messages from the "On My Mac" Trash folder?

Sure, each of my Mail accounts has individual settings for deleting old messages in its respective IMAP "Trash" folder, but, for whatever reason, some messages end up in the "On My Mac" Trash folder (instead of on server trash folders), where they sit until the cows come home (or I think to clean it out).

(Yes, I have checked each account's settings to make sure that none of them are set to use the On My Mac trash folder. I might have some rules which need to edited to use server trash folders, however.)