MailRecent now adds "Copy To Recent", "Move To Recent" and "Go to Recent" menu options to Apple's Mail app.
These menu items contain dynamically-updated databases of mailboxes that have been used recently. The "Recent Items" setting on the General panel of OS X System Preferences determines the number of mailboxes that are kept in the list.
Version 1.8:
Note: Now requires macOS 10.14 or later