The story on this is a question [1] was recently posed to the mailing
list about what's the different between "Recent Messages" and "Last 5
Days' Messages" as listed in the Show: combo box, and even I could not
answer before looking up the query expression for "Recent Messages" in
the source code (messages received in the past 24 hours, it turns out).
I can't defend why we need both options, and "Last 5 Days' Messages"
is less ambiguous and overlaps the results for "Recent Messages", so
"Last 5 Days' Messages" seems sufficient to me. There are numerous
ways to re-create the "Recent Messages" query if it's still desired:
saved search, search folder, or just sort messages by date received.
[1] https://mail.gnome.org/archives/evolution-list/2012-July/msg00044.html
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